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One eye.

B.

about fifteen days in the months of February or March)

they acquire another pair of feet; they are then the genus Thorax divided into many segments, as in Condylura. Nauplius of the same author. After their first moult they The anterior and much the largest segment presents a single assume the form and all the parts which characterize the eye only placed in the middle of the front between the supe- adult state, but with smaller proportions: their antenne rior antennæ. Cyclops (Müller), which has been so well and feet, for example, are comparatively short. At the end illustrated by the acute observations of the elder Jurine and of two more moulis they are fit for the reproduction of the of Ramdohr, is the only genus of this subdivision.

species. The greater part of these entomostraca swim upon The body of the Cyclopes is more or less approaching to their backs, darting about with vivacity, and possessing ihe oral, soft or rather gelatinous, and is divided into two por- power of moving either backwards or forwards, Their food tions. the one anterior, consisting of the head and thorax, the generally consists of animal matter in preference to vegeother posterior, forming what is commonly called the tail. table ; but in the absence of the former they feed on subThe seyment immediately preceding the sexual organs, and stances of the latter description, and it is said that the fluid which in the females carries two supporting appendages in in which they live never enters their stomachs. The alithe form of little feet (fulcra, Jurine), may be considered as mentary canal extends from one extremity of the body to the first segment of the tail, which is not always very clearly the other. The heart (aking Cyclops Castor as the subdefined or strongly distinguished from the thorax, and con-ject) is of a shape approaching to oval, and situated immedisists of six segments or joints, the second of which in the ately under the second and third segment of the body. Each males is provided on its lower side with two articulated ap- of the extremities of this organ gives off a vessel, the one pendages of varied form, sometimes simple, sometimes having going to the head, the other to the tail. Immediately a small division at the internal edge, and constituting en- below is another analogous organ, giving off also at each tirely or in part the organs of generation. In the other sex end a vess-l supposed to represent the branchiocardiac the female organ is placed upon the same joint. The last canals observable in the circulation of the Decapod Crustaseyment terminates in two points forming a fork, and more ceans. Jurine, who on many occasions reduced the Cyor less bordered with delicate beards or penniform fringes. clopes to a state of complete asphyxia and restored them to The anterior portion of the body is divided into four seg- life, found that in the process of reanimation the extremity ments, of which the first and by far the largest includes the of the intestinal canal and the supports gave the first signs head and a portion of the thorax, which are thus covered by of approaching animation, while the irritability of the heart one scale common to both. Here are situated the eye, four was less energetic, and that of the antennæ, especially in the antennæ, two mandibles (internal mandibles of Jurine) fur-males, of the feelers and of the feet still inferior. When a nished with a feeler (which is either simple or divided into portion of an antenna is cut off no change is effected at the two articulated branches), two jaws (the external mandibles time, but the organ is entirely restored in the succeeding or lip with little beards of Jurine), and four feet divided each moult. There are differences in the form of the antenna into two cylindrical stems, fringed with hairs or bearded. and body of Cyclops Staphylinus, and in the kind of horny The anterior pair representing the second pair of jaws differ process arising on the under part of its tail and curred backa litile from the succeeding pair, and are compared by Jurine wards, which led Latreille to consider it as forming a disto a kind of hands. Each of the three succeeding segments tinct subdivision ; and he seems to be of opinion that Cyclops - serves as the point of attachment to a pair of feet. The two Castor and some others, whose lower antennæ and mandisuperior antennæ are longest, setaceous, simple, and formed bulary feelers are divided, beyond their base, into two of a great number of small articulations. They facilitate by branches, may form another group. Calanus (Leach), he their action the motion of the body, and perform very nearly observes, may be a sub-genus, if it be true that the animal the office of feet. The lower antennæ (antennules of Jurine) which forms ihe type has no inferior antennæ ; but he seems are filiform, consisting most frequently of not more than to doubt whether this absence was made out by Leach's four joints, and are sometimes simple, sometimes forked. own observations, or whether the assertion is made on the By their rapid motion they produce a small eddy in the authority of Müller. water. In the males the upper antennæ, or one of them The genus Cyclops is an inhabitant of the fresh waters; only, as in Cyclops Custor, are contracted in parts, and ex- and we select the common Cyclops, Cyclops vulgaris, hibit a swelling portion which is followed by a hinge joint. Leach; Monoculus quadricornis, Linn.; Cyclops quudriBy means of these organs, or of one of them, the males seize cornis, Müller; Monocle à queue fourchue, Geoffroy, as an either the hind feet or the end of the tail of their females example of the species. in their amorous approaches: when these last are unwil The body of the common Cyclops has a somewhat swollen ling they carry the males about for some time. The copula- appearance and is formed of four rings, and prolonged to tion is prompt and reiterated. Jurine saw three acts in a about one-third of its entire length. The tail consists of quarter of an hour. Before his time, it was generally be- seven rings. The posterior antennæ (antennules of Jurine) lieved that the male organs were situated at the upper are tolerably large and composed of four joints, the anterior antennæ, an error which was supported by the analogy of antennæ are thrice the length of the posterior. those of the aruneids. On each side of the tail of the There are several varieties. females is an oval bag filled with eggs (external ovary of Var. a. Reddish; eggs brown, forming two oblique Jurine), adhering by a very fine pedicle to the second seg- masses near the sides of the tail. Total length eightment, near its junction with the third, and where the orifice twelfths of a line. This is the Monoculus quadricornis of the deferent egg canal may be seen. The pellicle which rubens of Jurine. forms these bags is only a continuation of that of the internal Var. b. Whitish or grey, somewhat tinged with brown, ovary. The number of contained eggs increases with age. rather larger than the preceding. Egg-masses greenish, They are at first brown or obscure, but afterwards present a forming nearly a right angle with the tail. Total length reldish tinge and become nearly transparent, without how the same as the preceding. This is the Mon. quadr. albidus ever increasing in size, when the young are about to come of Jurine. forth. When isolated or detached, up to a certain period at

Greenish. Direction of the two egg-masses least, the germ perishes. A single fecundation, which is intermediate between that of the egg-masses of the two indispensable, suffices for successive generations, and the former

. Length nine-twelfths of a line. Mon. quadr. same female can lay eggs ten times in the course of three viridis of Jurine. months, so that the number of births amounts to something Var. d. Smoky red. General form nearly oval. Eggs enormous. The time for the fætus to remain in the ovary brown composing two masses, which cover a great portion varies from two to ten days, the variation depending on the of the tail. Length six-twelfths of a line. Mon. quadr. temperature of the seasons and on other circunistances. fuscus of Jurine. The oviparous bags present sometimes elongated, glandiform

Var. e.

Of a deeper green than Var. c. Eggs obscure bodies, more or less numerous, which are supposed to be green, passing a little into rose-colour when hatching is congregations of infusory animalcules.

near, forming two masses attached to the tail, and appearing The young at their birth have only four feet, and their to be incorporate with it. Length the same as the precedbody is ounded and tailless. In tliis state they are the ing. Mon. quadr. prasinus of Jurine. genus Amymone of Müller, Some time afterwards (in According to Jurine's observations, the common Cyclops

when hatched is nearly splıcrical, and is furnished with Taking eight ovipositions and allowing forty eggs for each, it has been four feet only and but two antennæ. In this state it concalculated that one female Cyclope may be the progenitress of four thousand bre hundred millions.

tinues till the fifteenth day, and then a small elongation

Var. c.

с

takes place at the posterior part of the body. When twenty of each upper jaw as in the nature of feet, and excludes days old it acquires two additional feet, which are not how- from this number the presumed masculine appendages erer fully developed till the expiration of five days more. above mentioned, which he considers as filaments of five At the age of twenty-eight days it moults, and is not in a articulations proceeding laterally from the pouch of the condition to assist in the continuation of the species till it matrix, and of the use of which he is ignorant. The two has changed its skin a second time, when it takes its perma- antennæ are terminated by a pencil of fine hairs. The case nent form : this happens about the month of August. The or shell is suboval, arched, and protuberant on the back or female when once fecundated makes a succession of depo- hinge side, and nearly straight or a little sinuous or kidneysits of eggs without having occasion again to have recourse shaped on the opposite edge. A little in advance of the to the male.

hinge, and upon the mesial line, is the single large blackish

round eye. The antenne, which are inserted immediately 2

below, are shorter than the body, setaceous, composed of 1

from seven to eight joints, of which the last are the shortest, and terminated by a pencil of twelve or fifteen fine hairs, which serve as swimming organs. The mouth is composed of a carinated labrum ; of two large toothed mandibles,

each furnished with a feeler of three joints, to the first of de

which a small branchial lamina of five digitations (interior lip of Ramdhor) is attached, and of two pairs of jaws; the two upper, which are much the largest, have on their internal border four moveable and silky appendages, and

externally a large branchial lamina pectinated on its anbhab

terior edge; the second are formed of two joints, with a short, nearly conical, and jointless feeler, also silky at the end. A sort of compressed sternum performs the office of a lower lip (external lip of Ramdhor). The feet have five joints, the third representing the thigh, and the last the tarsus; the two anterior ones, much stronger than the rest, are inserted below the antennæ, directed forwards with stiff hairs on long hooks collected into a bundle at the extremity of the two last joints; the four following feet are without these appendages. The second pair, situated on the middle of

the under side of the body, are directed backwards, curved, 3

and terminated by a long strong hook bent forwards; the two last, never showing themselves beyond the shell, are applied to the sides of the body for the purpose of sustaining the ovaries, and are terminated by two very small hooks. There is no distinct joint observable in the body, which terminates posteriorly in a kind of tail, which is soft and bent upon itself underwards, with two conic or setaceous fila. ments fringed with three silky hairs or hooks at the end, and directing itself backwards so as to project beyond the shell. The ovaries forni two large vessels, simple and conical, situated upon the posterior sides of the body under the shell, and opening, one at the side of the otber, at the anterior part of the abdomen, where the canal formed by the tail establishes a communication between them. The eggs are spherical.

Generation. The mode of continuing the species is doubtful. Ledermüller declares that he has seen the junction of the sexes; but many modern naturalists whose attention has been particularly directed to the point have failed in discovering their sexual organs, and hare in vain watched for what Ledermüller declares he saw. Straus ob

served a large conical vessel filled with a gelatinous sub(Cyclops vulgaris magnified.]

stance inserted below the origin of the mandibles and 1, Malo of variety a; 2. female of the same: an antenow: sexual appearing to communicate with the esophagus by a straight organs of the male : cc. exterpal oviparus pouches of the female; dd, interuni ovaries; 3, a female of variety c, 4, a young individual of thal variety.

canal. As the individuals in which he detected this vessel

were furnished with ovaries, it would follow, if this organ Ostracoda, Latreille : Ostrópoda, Straus.

be a testicle, that the animals are true hermaphrodites; but The shell of the Ostracodu* is formed of two pieces or the vessel may be a salivary gland—that it seems to have

he himself expresses doubts upon the subject, allowing that valves representing those of a conchiferous mollusk or bivalve shell, but horny, not testaceous. As in the bivalves, more connexion with the digestive than the sexual functions

—and observing that the males can only exist at a certain the two pieces are united by a binge, and when the animal

time of the year. is inactiie they close upon and shut in the body and the

Habits.-These animals swim with more or less rapidity parts. The feet are ambulatory, six in number, and none are terminated by a digitated swimming organ, nor accom

in the still fresh waters or gently-running streams which panied by a branchial lamina. The antennæ are simple, cording to Jurine)'the filaments of the antennæ- sometimes

they inhabit, in proportion as they bring into action (ac.. filiform, or setaceous. posite and sessile. The mandibles and jaws are furnished they only show one, at others they put them all forth.

Latreille thinks that these filaments may also assist in with a branchial lamina, and the eggs are situated on the respiration. The two anterior feet are moved with the same back. of this division there are two subgenera, Cythere, Müller, when it creeps over the surface of the water plants, the

rapidity as the antenna when the animal is swimming : (Cytherina, Lamarek.) and Cypris. Of the former, which is found in salt and brackish waters, among the sea.weeds progress is slow. The female deposits her eggs in a mass, and confervæ, very little comparatively is known. We

fixing them by means of a glutinous substance on the water therefore select Cypris.

plants or on the mud. Anchored by her second pair of feet

so as to be safe from the agitation of the water, she is ocCypris has six feet; Ramdhor indeed allows but four, and Jurine gives eight. The first considers the two last cupied about two hours in this operation, the produce of as masculine appendages, and the second looks upon the which, in the largest species, amounts to twenty-four eggs. palpi or feelers of the mandibles and the branchial lamina Jurine collected some of these at the time of their ex

clusion, and, after having insulated them, obtained another to think, and not without reason, that Pentelasmis shows the greatest affinity which laid her eggs on the 12th of April changed her skin six

• Thompson observes that Mac Leay, in his Hora Entomologicæ, appears generation without the intervention of the male. A female with the Ostracoda, among crustaceans.

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times between that day and the 18th of May following: On, latter sort, which are most remarkable, are shown. &c. the 27th of the last-named month she laid again, and, two these are of the genus Cyclops. May not Baker have had days afterwards, made a second deposit. Jurine concludes Cypris in his eye when he wrote testaceous animaleules that the number of moults in the young state corresponds for when the valves are closed, it has all the appearance of with the gradual development of the individual. Desmarest an anephalous testaceous mollusk in a bivalve shell--and considers that they do not undergo a metamorphosis, but may not this be the passage alluded to by Bennet? The that they present, on their exclusion from the egg, the form following authors may be consulted on these animals, whose which they preserve throughout their life. Their food is highly curious organization and history have employed the said to consist of dead animal substances and of confervæ. pens of Linnæus, Joblot, Geoffroi, Müller, Ledermüller, In summer, when the heats hare dried up the pools, they Bennet, De Geer, Fabricius, Bose, Cuvier, Latreille, Dauplunge into the humid mud, and there remain in an debart, De Férussac, Lamarck, Straus, Jurine, Desmarest. apocryphal kind of existence till the rains again restore them to activity.

Cladócera, Latreille; Duphnides, Straus. The recent species are numerous; Jurine describes twenty one. Of these we select the largest, Cypris ornuta

These, which are very minute, have a single eye only. (one line and 2-12ths), Müller, for an external view, and and are protected by a shell doubled as it were, but witbout Cypris fusca (# of a millimetre), Straus, to show the internal any hinge, according to Jurine, and terminated posteriorly organization.

in a point. The head, which is covered with a kind of beaklike armour, projects beyond the shell. There are two antennæ, generally large, in the form of arms, divided into two or three branches, placed on a peduncle fringed with

filaments always projecting, and serving the purpose of B

oars. The feet are ten in number, terininated by a digitated or pectinated swimming organ, and furnished, with the exception of the two first, with a branchial lamina. Their eggs are situated on the back, and their body terminates with a sort of tail, with two delicate hairs or filaments at the end. The anterior part of the body is sometimes prolonged into the form of a beak, sometimes into a shape approaching that of a head occupied nearly entirely by one large eye.

Latreille gives the following subgenera : Polyphemus, Müller; Daphnia, Müller; Lynceus, Müller (Chilodorus, Leach). Of these, Daphnia is the most numerous subgenus, and though it is so extremely small, the observations of naturalists, and more especially of Schæffer, Ramdohr, Straus, and the elder Jurine, have rendered its organization and habits extremely well known. Straus, who has given

an excellent monograph of the Daphnida, adds two subCypris ornata (magnified). Shell yellowish green, handed, with green. A, side genera, Latona, characterized by antennæ in the form of view; B, view looking upon the hinge. The bands commence behind the eye.

oars divided into three branches, with a single joint
(Daphnia setifera, Müller); and Sida, with antennæ divided
into two branches, one of which has but two joints, while
the other has three (Daphnia crystallina, Müller). We
regret that our limits will not allow us to go into more detail
upon these interesting animals, and we must content our-
selves with referring to the authors above mentioned, with
the addition of Swammerdam, and Latreille, for particulars,
observing by the way that one junction of the sexes fecun-
dates the ova for many successive generations, six at least ;
that their moults are very frequent: that they lay at first

but one egg, then two or three, and so on progressively Cypris fusca (magnified), Straus. Valves brown, kidney-shaped, covered as they advance in life till their number amounts to 58 in with fine scattered hairs. Antennæ with fifteen fine bristles. In the view the

one species (Daphnia magna); and that the young of the valves are supposed to be removed, the outline a a showing their shape and their relative situation; b, origin of hinge membrane; c, eye; dd, antennæ

same deposit are generally of one sex, it being rare to find deprived of their bristles; e feet of the first pair ; fi of the second ; 9. of the two or three males in a female batch, and vice versa. As n, of the second pairs,., branchia or gill; p q posterior portion of the left and the frost is supposed to destroy them, leaving however third pair; h, tail; i, labrum; k, mandible; 7. feeler; m, jaw of the first pair; the winter approaches, their moults and oviposits cease, ovary; r, insertion of the vessel regarded as a testicle by Straus. Fossil CYRRIS.

the eggs unharmed, which the genial spring season batches

to fill the pools with myriads of Daphnia. Then those Cypris Fuba, Desmarest, holds a place among the organic who have microscopes will find ample employment for them. remains of the Wealden rocks of England. Dr. Fitton has Every ditch, every pool, every garden reservoir, will furnish recorded it in the Weald clay of the Isle of Wight, Swanage the observer with Branchiopods. Bay, &c., and Mr. Mantell in the Hastings Sands. The species are numerous. The most common is the Desmarest notes the species as found in great abundance Water-flea, Monoculus Pulex of Linnæus, Pulex aquaticus near the mountain of Gergovie, in the department of the arborescens of Swammerdam, Le Perroquet d'eau of GeofPuy de Dôme, and at the Balme d'Allier, between Vichy-froy. Despised as this minute creature may be by those les Bains and Cussac. Their great fruitfulness and the who, like the orientalists, consider size as absolutely necesfrequent moults noticed above may account in some mea- sary to produce grand ideas, it was fixed the especial attensure for the quantities of their petrified exuviæ. Cypris tion of Swammerdam, Needham, Leuwenhoek, Schæffer, has also been found in the fresh-water limestone, beneath De Geer, Straus, and above all of Jurine, who, in common the Midlothian coal-field, at Burdiehouse, near Edinburgh, with other philosophers of great name, have found as much

Straus observes that Bennet asserts Baker to be the first interesting information regarding the development of ani, author who has mentioned this crustaceous form, and that mal life in the admirable organization of these animated Baker has given a figure of it in the Microscope made specks as is afforded by the largest vertebrated animal. Easy,' at plate 15; but Straus adds that neither in the

SECTION II. edition of 1743, nor in that of 1744, is any account given of it, and that there is no 15th plate. There certainly is no

Phyllopa. plate 15 in the edition of 1744, nor any figure or des ption Distinguished by the number of feet, and by the lamelthat will accord with Cypris, while there is, at plate 9, a lar or foliaceous form of the joints, representing, according very fair representation, and at p. 93, a very fair account of to Latreille, the Myriapods in the class Insects. The eyes Cyclops. Baker commences his account of the latter thus: are always two in number, formed of a sort of network, and • We may find in the waters of our ditches several species sometimes placed on pedicles; many have besides a single both of testaceous and crustaceous animalcules, two of these I smooth eye.

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a.

motions of their respiratory paddles render them very inCeratophthalma, Latreille.

teresting objects, and convey a deep impression of the The Ceratophthalma have ten pairs of feet at the least, harmony of adaptation of members to two such apparently and the maximum of those organs in this group is said to anomalous ends as breathing and locomotion at the same

moment. be twenty-two. There is no vesicular body at their base, and the anterior feet are never so long as the others, nor are

The salt-pans at Lymington and some salt lakes in Sibethey ramified. The body is either enclosed in a shell case, ria appear to be the only localities where these animals have like a bivalve shell

, or naked, the thoracic divisions being been hitherto detected. For further particulars we must reeach furnished with a pair of feet. The eyes are sometimes fer to Mr. Thompson's memoir; and as our limits will not sessile, small and placed very near together; sometimes, and allow us to devote more space to this highly-interesting indeed most frequently, they are mounted on the extremity group, we select Branchi pus as a proper vehicle for convey of two movable pedicles. The eggs are either internal or ing some idea of the organization of these crustaceans to external, and inclosed in a capsule,

the eye of the reader.

Branchipus then, if we adopt the views of Mr. Thompson,

and consider Branchipus paludosus, a native of the swamps Eyes sessile, immovable. Body inclosed in an oval case in Greenland, and about three quarters of an inch in length, like a bivalve shell. Ovaries always internal.

as a fourth species of Artemis, will offer but one species, The sub-genus Limnadia of Adolphe Brongniart is an Branchipus stagnalis, Cancer stagnalis of Linnæus, Gamexample of this structure. Limnadia Hermanni, Adol.

marus stagnalis of Fabricius and Herbst, Apus pisciformis Brongn., Daphnia gigas of Hermann, occurs in great num of Schæffer, who found it in a ditch by the road which bers in the little pools of the forest of Fontainebleau, and leads from Ratisbon to the town of St. Nicholas. we must refer the reader to Brongniart's memoir in the sixth vol. of the · Mémoires du Museum d'Histoire Naturelle' for its description.

B. Each eye situated at the extremity of a pedicle on both sides of the head. Body naked and annulated throughout

3 its length.

No enveloping case or shell. Eggs contained in an elongated capsule situated towards the base of the tail, or at the posterior extremity of the body and thorax in those which have no tail.

1.

With a Tail. To this subdivision belong the Brine-shrimp or Brineworm, Artemia, or Artemis, Leach,-Branchipus, Latreille,

2 and Chirocephalus, Benedict Prevost and Jurine. We are now arrived at that development of form in the Branchiopods where the numerous legs or feet become paddles adapted simultaneously to the purposes of locomotion and respiration.

The Brine-worm or Brine--shrimp, Cancer Salinus of Linnæus, Gammarus Salinus of Fabricius, Artemis* Salinus, Leach, Artemisus Salinus of Lamarck, when full grown is about half an inch in length and very transparent : it is said to have been first discovered in the saltpans at Lymington by Dr. Maty. There these animals are found in myriads in rapid and continual motion in the salterns, which are the open tanks or reservoirs where the brine is deposited previous to boiling. The brine attains the desired strength

1. Branchipus stagnalis, male (magnified); a, a, composite or network eyes; by evaporation from exposure to the sun and air in about 6, antenne : 6,c, mandibuliform horns; d.d. proboscidiform, movable ieu: a fortnight. A pint contains about a quarter of a pound tacula, rolled opirally ; e, simple rudimentary eye : 1,5, lear-like natatury feet of salt, and in this concentrated solution, which, as Mr.

or oars ; 9, male organs; k, h, tail; i, i, terminating filaments ; 2, frout view of

the head ; 3. tail of the female; k, egg-pouch ; 7, femule organ; 1, a young Rackett observes, instantly destroys must other marine Branchipus after the first moult. animals, the brine-shrimp revels. It is further said that

2. these Brine-worms are never found in the sun-pans where

Without a Tail. the brine is made by the admission of sea-water during The genus Lulimene, Latreille, belongs to this subsection. the summer, and which are emptied every fortnight, but The body is nearly linear, and there are four short antenonly in the pits or reservoirs (clearers) where it is depo. næ almost @liform, of which the two smallest, which much sited after it is taken out of the pans, and where some of the resemble feelers, are placed at the anterior extremity of the liquor constantly remains. So persuaded are the workmen head, which is furnished with two eyes mounted on cylinof their utility in clearing the liquor, that they are accus. drical pedicles. The branchial paddles are eleven, and tomed to transport a few of the worms from another saltern, immediately behind them is a terminal demi-globose piece in if they do not appear at their own, and they increase greatly place of a tail, from whence issues a long, delicate, ihreadin a few days. "Little however was known of the natural like process, which may perhaps (according to Latreille) be history of this animal till Mr. Thompson published his in- an oviduct. Eulimene albida, whose body is for the must teresting observations in the sixth number of his · Zoological part white, with its posterior extremity black (Artemia EuResearches' (1834). He has there described and illustrated limine, Leach), the only species described by Latreille, was the gradual development of the embryo, and the meta- found in the Mediterranean near Nice. morphoses which it undergoes from its first production until it arrives at a perfect or adult state. These, he says, will

Aspidophora. be found to correspond with those of Branchipus, Chirocephalus and Apus, animals with which its alliance can no

of this last division of the Phyllopa, Latreille says that longer be doubtful. Artemis bears a long journey very well. they have sixty pair of feet, all furnished near their base We have had a glass jar full of them in their native brine with a large oval vesicle, the two anterior feet, which are sent to London. They lived a considerable time and were much the largest, resembling antennæ. A large shell or in full life and activity, affording very satisfactory opportu- crust corers the larger portion of the upper part of the body. nities of observing their habits and of confirming the state. This shell is free, shield-shaped, notched posteriorly, and ments of Mr. Thompson. They are constantly gliding with bearing anteriorly on a circumscribed space three simple an even motion in the clear circumambient fluid, sometimes sessile eyes, which the two anterior are largest and lunuon their backs, sometimes on their sides, sometimes on their lated. There are two bivalve capsules containing the eggs bellies, and seem to more with equal facility in every direc- and annexed to the eleventh pair of feet. tion, Their transparency and the unwearied undulating

Apus productus (see BINOCULUS, the figure of which

has been reversed by the printer) is an example. Mr. Lamarck justly observes upon Leach's original name, that Artemisia had heen already appropriated to a genus of pianis. Poli

has applied the term Thompson figures a species, Apus Guildingi, from the West Artemis to a conchiferous mollusk allied to Cytherea, &c,

Indies, and observes that there appear to be two Europeun

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species confounded under the gpecific name cancriformis, , tral dominions of the reigning family; the Mark itself being viz., Scheffer's and Dr. Leach's, which most resemble indebted for its own denomination to the ancient t. of that Apus Guildingi and that described by Savigny, in which name. Its component parts, however, are not what they the elongated shield entirely covers the natatory members. were in former days ; for the N.W. districts of the Electoral

Mr. Thompson observes that there is a considerable ap. Mark (Kurmark) and the Alt-mark (Old-m.) have been in. proximation between Artemis and certain Trilobites (Bu- corporated with the prov. of Saxony ; and the northern parts cephalithus, &c.), nor can there be any doubt that the ana- of the Neumark, adjacent to Pomerania, have been united logies of Branchipus, Serolis and Limulus all contribute to with that prov. In exchange for these, several minor circles, the illustration of that most ancient race of crustaceans. bailiwicks, and other parcels of land, all of them once formWe have not, as yet, data sufficient to fix their proper posi- ing a portion of the districts of Wittemberg, Meissen, Quertion. but there is every reason for supposing that their or- furt, &c., in the kingdom of Saxony, are now comprised in ganization was constructed upon the principle of having the Brandenburg. With the exception of two insignificant same organs made subservient both to locomotion and respi- tracts, surrounded by the territory of Mecklenburg-Schweration. [Txilobites.]

rin, the prov. forms a compact mass. Its boundaries are, in BRAND or BURN. Brand, a disease in vegetables by the N., the two grand Duchies of Mecklenburg-Schwerin whirh their leaves and tender bark are partially destroyed and Strelitz, and the Prussian prov. of Pomerania: in the as if they had been burnt; hence the name of this disease, E., the provinces of Western Prussia. Posen, and Silesia; in which is called brûlure in French. It has been observed the S. the provinces of Silesia and Saxony, and ihe Anhalt that after the leaves have been wetted by dews or gentle principalities; and in the W. the prov. of Saxony, and the rains, so that drops adhere to them, nd a bright sunshine Hanoverian dominions. Brandenburg thus extelids between has succeeded, every spot to which the water had adhered 51° 10' and 53° 37' N. lat. and 11° 13', and 16° 12' E. lung. lost its natural colour, and became of a dark or yellow hue; Its area is about 15,330 sq. m., and occupies about a seventh and on closer examination it was found that the organiza- part of the whole surface of the Prussian dominions ; it tion had been partly destroyed, and that these spots no ranks as the fourth prov. vith reference to density of pop. longer possessed the power inherent in healthy leaves of The whole of Brandenburg is an almost uninterrupted ex haling water and carbonising the sap which circulates plain, slightly elevated above the surface of the Baltic. Its through thern. When this disease is extensive and attacks soil is composed of river sand, in some quarters mingled the bark as well as the leaves, it frequently causes the with ferruginous earth, loam, or clay, and hence arises so death of the plant, and, at all events, enfeebles its growth, great a diversity in its character, that a general failure of and prevents its perfect fructification. The cause of this, crops is almost unknown; for a sea-on unfavourable to one like that of most diseases which are common to plants, has part is usually found proportionably beneficial to another. been vulgarly ascribed to some unknown atmospheric in- | The more elevated and undulating parts of the surface, fluence; and various guesses hare been made which, for the which are most frequent in the S. districts, between Frankmost part, have little or no foundation. That which ap- fort on the Oder and the Silesian frontier, are improperly peared most plausible was, that the drops of water being called mountains. by the inhabitants; among these are the apparently globular, collected the light of the sun into a Oderberge (m. of the Oder), the Neiss and Schlagsdurlerfocus, and produced a sufficient degree of concentration of berge, in the vicinity of Guben, the Müggelsberge on Lake the calorific rays to burn the tender substance of the leaves. Müggel. about 8 m. S.E. of Berlin, 340 ft. in leight, and A little retlection will soon convince us that this will not the heights which run along the Havel. These are probear examination. The drops which adhere to the leaves minent features however in the midst of a wide and weariand the bark are not globes, but at best flattened hemi- some fat, and intermingling with numerous lakes, many of spheres, and consequently cannot collect the rays of the them lying in deep hollows, form landscapes of considerable sun into a focus on the surface to which they adhere; besides, variety. Of the larger class there are not fewer than 1:31. the spots are as large as the diameter of the drops, so that the most fertile districts are the low lands, termed the all the surface that has been covered with water is injured ; Havelland, the Brüche (or Carses) of the Oder, Warth, and whereas the focus of a globe, such as would actually burn Netzel, the Spreewald (wood of the Spree), the N. and E. the leaf, must be very small in proportion to the lens which parts of the Ucker-mark, the Lenzerwische on the Prieg. concentrated the rays. It is much more probable that the nitz, and what is denominated the · Alte Land' (Old land) effect of the water on the tender epidermis of the leaf or bark in Lower Lusatia. But Brandenburg contains many exto which it adheres is similar to that which it has on vegetable tensive heaths and moors, here called “Brennflächen or matter infused in it; it softens and dissolves a portion of it, burning flats), which are a collection of drift sand, the culespecially when the temperature is somewhat raised, and tivation of which has often bailled the utmost efforts of indestroys the vitality; galvanic action may also be excited dustry. The climate of Brandenburg is temperate, but exand increase the effect. It is well known that light is the ceerlingly variable : the result of several years' observations great agent which produces the change in the sap circu- fixes the maximum of heat at between 24° and 25° Reaulating in the leaves, and that without light the healthy mur (86° and 88° of Fahrenheit); the maximum of cold is green colour af the leaves and bark, and the peculiar qua- said to be — go R. (18° below freezing of Fahrenh.), but the lities of the descending sap, are not produced. Little or no temperature is rarely so low as this for more than three or evaporation takes place from the leaves in the night, and four days. It is also stated, that upon a comparison of one the sudden excitement produced on the whole of the surface year with another, there are 210 clear, dry, and 155 damp of the leares by the rising sun in a clear morning tends to and rainy days. disorganize those parts to which the water adheres. We do not give this as a perfect and adequate solution of the principal streams of Germany; the Elbe, which forms its question, but it appears nearer the truth than any of those N.W. boundary for a short distance, and the Oder, which more commonly received. (De Candolle, Physiologie végé- drains its E. districts. The Elbe skirts Brandenburg only tale, vol. iii. chap. iv. s. 2.)

from Sandau to Dömitz, and on this line of its right bank It is a fact that the principal mischief arises from a receives the Havel. Stepnitz, and Elde. The number of sudden change of temperature soon after sunrise, especially tracts of land, lower than its surface, which abound in this when there has been a heavy dew or hoar frost in the quarter, are protected from inundation by artificial dykes. night; and careful gardleners brush off the drops from The Havel, which is a channel for the efflux of the Böblitz their delicate plants before sunrise to guard against the and other small lakes in Mecklenburg-Strelitz, becomes brand. Every drop which falls on the leaves of tender navigable at Fürstenberg, below which point it enters plants from the glass which covers a hotbed in which they Brandenburg: it then flows past Liebenwalde. Oraniengrow produces a disease exactly similar to that which we have burg and Spandau; and thence taking a W. direction been describing; and although the vapour of fermenting through Potsdam, and the town of Brandenburg, it turns dung has a pungent, ammoniacal smell, i' will be found that to the N. W. at Plauen, where it is joined by the canal the water condensed on the glass is nearly pure, and can of that name, skirts Rathenow and Havellierg, and have no peculiar corroding effect. It acts therefore simply falls into the Elbe by two arms, between Havelort and as a dissolvent, and by stopping the evaporation, which is Quitzöbel. It passes through a low tract of country, in always rapid from the leaves of plants in a hutbed, produces which sand, woodlands, and pasture-grounds alteriale; a derangement in their functions, and ultimately disease. its width at Oranienburg is 100 lt., and at Spandau 2000, BRAND IN CORN. [Burnt Ear.)

in consequence of passing through several lakes ; below BRANDENBURG, a prov. of the kingdom of Prussia, Brandenburg it narrows again to 200, and at its mouth inderives its name from the Mark of Brandenburg, the ances creases to 500. A branch of it strikes off at Brandenburg

: a Brandenburg is either traversed or skirted by two of the

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