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comprehensive, and includes a thorough knowledge of the

II. NATURAL PHILOSOPHY. elements of the chief subjects of a good general education. It The University Calendar states that the knowledge required is conducted by printed papers containing questions to be of natural philosophy is such as may be attained by attending answered in writing; and although the examiners have power a course of experimental lectures on the elements of mechanics, to put viva-voce questions, this is very seldom done. The hydrostatics, hydraulics, pneumatics, acoustics, and optics. preparation for passing the examination will demand some But this information is deceptive. Attendance at such a conscientious work, and since the statistics of the university conrse of lectures is highly desirable for the sake of the show that nearly half the candidates who present themselves illustrative experiments, but the subject will also demand confail to satisfy the examiners, we recommend our students to siderable reading and study. The fact that the examinational study diligently and to test their own knowledge carefully statistics of the university show this paper to be a very fatal before presenting themselves for examination, and incurring the one to candidates confirms the opinion we have expressed, and risk of rejection. It must also be remembered that although induces us to recommend great attention to the principles of a the classification of those who pass is dependent on the total subject which is not susceptible of being crammed. Whichever number of the marks gained for their papers, candidates must work upon the subject may be selected should be read thoughtsatisfy the examiners by obtaining at least the minimum of fully and with attention, and the principles of the several scimarks in each of the several branches, and that numerous cases ences should be so thoroughly mastered that they may be readily occur at each examination in which failure is to be attributed applied to the solution of the questions submitted in the to deficiency in only one of the many subjects. Of these examination-room.* natural philosophy and chemistry appear to be the most fatal, In mechanics the student must be able to explain and and we recommend that attention be paid to them.

illustrate the theory of the composition and resolution of The chief branches of the examination are mathematics, statical forces,t to describe the simple machines, i.e., the pulley, natural philosophy, chemistry, classics, the English language the lever, the inclined plane, and to answer questions depending and history, and either French or German; and of these we

on the ratio of the power to the weight in each. I The principle shall speak in order.

of the centre of gravity, the general laws of motion, and the I. MATHEMATICS.

law of the motion of falling bodies,|| must also be thoroughly This branch includes-1. Arithmetic. 2. Algebra. 3. Geo- understood, and the chief experiments illustrative of them must metry.

be made so familiar to the student's mind that he may be able The questions in arithmetic and algebra form the subject of to describe them readily on paper. one paper, for which three hours are allowed.

In hydrostatics, hydraulics, and pneumatics the Calendar 1. Arithmetic. The arithmetical questions usually set involve directs attention to the pressure of liquids and gases, its equal a knowledge of numeration and the theory of numbers, in diffusion and variation with the depth, and to specific gravity, ** addition to which the Calendar specifies "the ordinary rules," and the modes of determining it. The principles of the action which must be held to include those which are known as the of the barometer,tt the siphon, 11 the common pump and forcing first four rules, simple and compound, direct and inverse pro- pump,$s and the air pump|||| must also be studied, and, if posportion, simple and compound interest, discount, the purchase sible, the action of these instruments should be observed with a of stocks, etc. The preponderance of questions in interest, view to a written description of their working. rule of three, and discount renders it desirable that special

The knowledge of acoustics required is limited to the nature attention should be paid to these rules. The addition, subtrac- of sound, and of optics to the laws of reflection and refraction, tion, multiplication, division, and reduction of vulgar and and the theory of the formation of images by simple lenses. TT decimal fractions,t and the extraction of the square root, must The student is

, however, advised to familiarise himself with the also be carefully studied. Most of the ordinary school arith general principles of these sciences, since the omission to do so metics will contain the information requisite in this branch, and may prove embarrassing at the examination, and the knowledge of these Hudson's is perhaps the best.

acquired will certainly not only prove useful, but, from the 2. Algebra.-In algebra knowledge is required of the proposition which science is assuming as a prominent branch of cesses of simplification, addition, subtraction, multiplication, and general education, will at no distant dato be considered essential division of algebraical quantities, and some facility in perform- in a well-educated member of society. ing these operations and in the solution of simple equations and easy problems involving them must be acquired.I Arithmetical

COMPARATIVE ANATOMY.-XX. and geometrical progression, the formulæ of which should be remembered, and algebraical proportion must also be read, and

BIRDS. their rationale mastered.

This class of the vertebrates, though possessing an external 3. Geometry. The first four books of Euclid are the subject configuration which apparently differs much from all other of a three hours' paper on geometry, which usually comprises animals, is closely allied to, and may be considered as an one or more propositions from each book, with simple deductions extremely modified reptilian type—the tiro constituting a great from them. It is not, however, essentially necessary, though order, which Huxley calls Sauropsida. highly desirable, that the latter should be done. The proposi The rule, that animals are constructed according to their tions should be rendered perfectly familiar, in order that they habits and the medium in which they live and move, is beautimay be readily written and that time may be devoted to the fully exemplified in birds. Their bones are extremely light, exercises upon them, which may require some thought. It is and rendered still more so by being, in the majority of instances, scarcely necessary to caution the student against merely com- permeated by air. The outer covering, or epidermis, which in mitting the words and figures to memory without mastering the the preceding divisions we have seen variously modified, also various steps in the reasoning process.

undergoes a wonderful change, thus contributing to the same The examiners merely require that the latter shall be made end, and exhibiting a characteristic difference from the scalemanifest. A symbolical Euclid will be useful to the student, clad, cold-blooded animals we have described. The cuticle but, as few abbreviations are permitted at the examinations, it is appears no longer as scales, but as closely aggregated appendnot desirable that it should be read alone.

ages, or feathers, which closely envelop the body, for the double The less conventionally Euclid is studied the better, and we recommend the student to construct carefully his own state. Haughton, M.D., will be found a useful work in preparing for the

* The "Elements of Natural Philosophy," by the Rev. Professor ments and diagrams of the various propositions. This is a

examination. The Lessons in Natural Philosophy in the POPULAR. work involving some time and thought, but its value is un

EDUCATOR will also prove extremely useful. questionable. Il

+ POPULAR EDUCATOR, " Lessons in Mechanics"-III.

* "Lessons in Mechanics"-VIII.--XVIII, See POPULAR EDUCATOR, "Lessons in Arithmetic," I. XVIII. $ “Lessons in Mechanics"--V.-VII. + POPULAR EDUCATOR, "Lessons in Arithmetic,” XIX.-XXV.

# "Lessons in Mechanics"-XXII.-XXIV, POPULAR EDUCATOR, " Lessons in Algebra," 1.-XII.

["Hydrostatics"-I., II. Galbraith and Haughton's "Manual of Algebra" is a good work ** "Hydrostatics"-III., IV. H "Pneumatics"--III. for the purpose of preparation.

11 “Pneumatics"-II.

$6 "Hydrostatics "_VII. See the "Lessons in Geometry," in the POPULAR EDUCATOR,

11:11 “Pneumatics"-I.

17"Recreative Science"-I.-IV.

purpose of maintaining warmth, and assisting in aerial pro- of the simple reptilian form. It varies from twice to eight. gression. Each feather is, as Paley truly observes, a mechanical times the length of the body. The first portion of the intestine, wonder. When fully formed, a feather is composed of a central immediately succeeding the stomach, is called the duodenum, cylinder or quill, by which it is attached to the skin ; a shaft, and is arranged in a characteristic loop-like fold, the interval which is the tapering continuation of the quill; and the vane being occupied by a gland called the pancreas, which is similar or beard which projects from each side of the shaft. The latter in structure to the salivary glands. The remaining portion is is composed of barbs and barbules. The feathers present some also more or less folded, but in an irregular manner, and finally variations in size and form in different parts of the body. They terminates in a short tabe of greater calibre, called the large are variously coloured, and form the chief feature of ornamental intestine. In the mammalia, the large and small intestines are beauty of birds. The feathers are formed by the conversion of separated by a valvular fold of the mucous lining; in birds, the cells of the outer layer of the epidermis (skin) into horn-like however, there is no such arrangement. The point of terminamaterial.

tion of the one and commencement of the other is marked by The Mandible or Bill consists of two portions, formed by the one or two pouches called cæca (Fig. III., 6), one on each side of elongated upper and lower maxillary bones, covered over with a the intestine. They vary in length from a simple offset, as in horny sheath, which serves the place of teeth. Besides being the Soland goose, to processes three feet in length, as in the a prehensile organ, the bill aids in the masticatory process to a grouse. The interior of the cæca of the ostrich is arranged in certain extent, and in some birds, e.g., the parrot, assists in a spiral manner. The cæca are wanting in many birds, as the climbing, thus acting as a third foot. It presents many inte. cormorant, Wryneck, toucan, some vultures, etc. The large inresting modifications of size and shape, from the filamentous testine is short, straight, and destitute of folds, and terminates. cone of the humming-bird to the huge bill of the toucan. The in the cloaca (Fig. III., 10). There is an appendage (Fig. III., food, and manner of obtaining it, peculiar to each species, 11) connected with the small intestine, the remains of the duct of determines the size, shape, and degree of hardness of the bill. communication between the yolk-bag and intestine in the chick. Thus it is strong and hook-like in those which tear their prey; Birds have no diaphragm or partition-muscle separating the short and conical in the grain-eaters ; probe-shaped in those thorax from the abdomen ; consequently, the liver, which is large which live principally on insects. In the ibis, the bill is curved and two-lobed, occupies a part of both cavities. It has appended down. In the jabiru (Fig. I., c.) it is bent up. It is dilated at to it a gall-bladder and a bile-duct. The latter opens into the the extremity in the spoonbill. Ducks, geese, etc., have their first part of the small intestine, and the fluid which it conducts bills flattened. In some birds it is dentated. Besides these, plays an important part in the digestive process. The spleen there are a variety of shapes, extremely interesting.

is small. The kidneys are large, and lodged along the upper The Tongue presents almost as many peculiarities as the part of the pelvis. From each kidney a tabe—the ureter (Fig. mandible, and like it serves for the most part as an organ of III., 8)-passes downwards, terminating in the cloaca. Birds prehension. It is composed of muscles, covered with a horny have no urinary bladder, the urine being voided along with the sheath, and supported by one or two bony pieces (hyoid appara-excrements. tus), prolonged backwards behind the head (Fig. VIII.). This The Respiratory Apparatus.—This consists of an air-tube (the hyoid apparatus is very remarkable, especially in those birds trachea), with an upper and lower larynx, two lungs, and a which dart the tongue rapidly at insects, as the woodpecker number of air-sacs variously disposed throughout the body. (Fig. VIII.). In the latter, the tongue is armed at its tip with The trachea, or wind-pipe, is a cylindrical tube, composed of sharp-pointed processes for transfixing insects. In the fieldfare a number of cartilaginous rings connected together by fibrous (Fig. II., b.) the horny sheath of the tongue terminates in fine membranes. Its length accords with that of the neck of the filaments. In the snipe (a) it is long and slender. It is very bird. It is surmounted above, and also below, by a laryns. short in the kingfisher (d). The tongue of the goose (c) has The upper larynx is homologous in position, and in some respects projecting from its sides a number of recuryated spines. The in structure, with the mammalian larynx. But not in function. honey-eaters have the extremity of their tongue furnished with The lower one is the true larynx, from whence emanate the a tuft of horny, hair-like filaments. These peculiar shapes of sweet songs by which the feathered tribe relieve the monotonous the tongue are, liko the mandibles, determined by the kind of stillness of country life. food, and the method of obtaining it. Beneath the tonguo The rings which enter into the formation of the air-tube are there are a number of small cellular masses, called salivary not invariably of a uniform diameter, but sometimes present glands. These furnish a gummy-like Auid (saliva), which eccentric arrangements, as in the turkey, heron, eagle, etc., moistens the food. In the woodpeckers, and other insectivora, increasing in size from above downwards. Sometimes the the saliva is viscid, to enable them to entrap insects.

windpipe is found of a fusiform shape, thicker in the centre Alimentary Canal.—The first portion of the digestive tract, than at the extremities; or it may be convoluted at the root of extending from the mouth to the stomach, is called the gullet. the neck. Sometimes one or more chamber-like dilatations are Its length is proportionate with the bird's neck. It is usually found developed upon it. wide, and in some birds capable of great distension. At the The lower and true larynx is situated upon the inferior lower part of the neck it communicates with a receiving cavity extremity of the trachea, just before its bifurcation into the or crop (Fig. III.), where the food, after swallowing, remains bronchi. This complex apparatus will be best understood by : lodged for a time. A little below the crop there is another reference to Fig. VII., a, 6 (after Milne-Edwards). It may be dilatation, the proventriculus, or second stomach (Fig. III., 3), compared to a kind of osseous drum, the interior of which is and below this a third, the gizzard. The crop is a temporary divided inferiorly by a traversing beam of the same nature, reception-bag, the food lodging there until the gizzard is ready surmounted by a thin semi-lunar membrane (Fig. VII., b, 2). to receive it. It is single, but of large size in the common This drum communicates inferiorly with two apertures of the fowl (Fig. III., 4). The pigeon has a double crop. In many glottis (rimæ glottidis), formed by the termination of the bronchi, birds it is wanting, the food passing along the gullet to the true and each provided with two lips, or vocal cords. Finally, muscles, stomach at once, or, as in some birds that swallow whole fish, the whose numbers vary with the species, extend between the difgullet is distended into a pouch-like cavity, serving the pur-ferent rings of which these parts are composed, and move them pose of a crop. The proventriculus (Fig. III., 3) may be smaller so as to stretch more or less strongly the membranes they supor larger than the gizzard. Its walls are thickly studded with port. In birds which do not modulate the sounds, the memsmall follicles called gastric glands, which pour out a fluid to branous septum is wanting. In those which do not sing there macerate the food, and to reduce it to a condition more readily are no muscles proper to the inferior larynx (Milne-Edwards). acted on by the gizzard. The gastric glands are variously The lungs are small and undivided. A subdivision of the arranged, and present some differences in size and shape. Some trachea (bronchus) enters the inner and lateral aspect of each of these are shown in Fig. IV., a, b, c, d, e.

lung, and after traversing the lang by smaller subdivisions. The gizzard, composed of a dense aggregation of muscular (Fig. V., aa, bb), communicates on their inferior surface, by four fibres, is covered on its internal aspect by a dense skin-like mem- or more pairs of orifices, with the air-saos of the body. The brane, thus forming a powerful agent for the

mechanical redac- latter communicate with the interior of the bones. Respiration tion of the food. Many birds further increase the power of reduc- is thus seen to be a very active and complicated process in birds, tion by swallowing pieces of flint, or other hard substances. and not confined

to the lungs, but shared in by every part of the The intestinal portion of the alimentary canal retains much body where air penetrates.

Circulation. The temperature of the blood exceeds that of enlargements where the nerves emanate to be distributed to the any other vertebrates, ranging on an average from 100° to 109° extremities. or 110°. In sea-birds, as the gull, the temperature is lower The Skeleton.-The skull of birds is made up of a number of than that of other birds, varying from 100° to 105°. In the bones, separate in the young bird, but which, speedily growing, common fowl it ranges from 107° to 110°. In the swallow it become inseparably blended together in the adult. The jaws, is said to be as high as 111. The blood-corpuscles are for as already mentioned, are elongated, and both are movable. The the most part red, and nucleated.

lower one is connected to the cranial bones by the intervenThe heart is double, each one presiding over a separate tion of a second one called the tympanic or quadrate bone. system; the right one over the pulmonary, the left one over | The skull is connected to the vertebral column by means of a

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BEAKS 07 (a) SHRIKE, (6) CROW, AND (e) JABIRU. II. TONGUES OF (a) SNIPE, (b) FIELDFARE, (c) GOOSE, AND (a) KINGFISHER. III. DIGES

TIVE CAXAL OF COMMON Fowl. IV. GASTRIC GLANDS IN (a) EAGLE, (6) PIGEON, (c) Swan, (d) RHEA, AND (e) OSTRICH. V. DIAGRAM OF LOBULE OF BIRD'S LUNG. VI. FEMALE ORGANS OF Fowl at BREEDING SEASON (Owen). VII.a. INFERIOR LARYNX OF Rook. VII.6.

VEXICAL SECTION OF INFERIOR LARYNY OF Rook. VIII. HEAD OF WOODPECKER (MILNE-EDWARDS). #s, to Nor. in Figs.-III. 1, gullet ; 2, crop ; 3, proventriculus ; 4, gizzard ; 5, small intestine ; 6, cæca ; 7, large intestine; 8, 8, ureters ; 9,9, oviducts; 10, cloaca ; 11, process for attachment of yolk-bag. V. aa, subdivisions of bronchus; 66, smaller subdivisions. VI. 1, ova, or yolks ; 2, vascular membrane of calyx; 3, zone, or stigma; 4, empty calyx; 5, infundibulum; 6, 6, oviduct; 7, oblique ridges of lining membrane of oviduct; 8, shell-forming dilatation ; 9, egg exposed ; 10, villi, containing follicles concerned in the secretion of shell ; 11, con. volutions of oviduct; 12, cloaca. VII.a, 1, trachea ; 2, drum formed by the lower end of trachea ; 3, middle ossicle ; 4, first ring of the bronchi; 5, bronchi; 6, proper muscles of the larynx ; 7, depressor muscles of the trachea. VII.6. 1, inferior portion of the trachea. divided as regards the half ; 2, semi-lunar membrane ; 3, osseous cross-bearer ; 4, little rim formed by internal lip of the right glottis ; 5, inner surface of right bronchus, formed by a tympaniform membrane ; 6, portion of the cavity of the right bronchus exposed by a section of part of this membrane. VIII, 1, hyoid apparatus ; 2, tongue.

general or systemic. The main object of the right system single condyle. The vertebræ vary in number, the cervical lo remove from the blood carbonic acid, which results from ranging from ten to twenty. The dorsal, lumbar, and sacral waste-tissue products, and replace it with oxygen.

vertebræ are generally found fused together and immovable. Nervous System. The brain of birds makes some little The coccygeal, which support the tail, are movable. The rance towards the mammalian character. The cerebral sternum, or breast-bone, is large and expanded, and has pronispheres are increased in size, and possess traces of conjecting in the median line a keel-like ridge, to increase the surutions. The ganglia which preside over the sense of taste face of attachment of the large elevator and depressor muscles small. The optic lobes are large, as might be articipated of the wing. It has connected with it two bones ; one small,

the keen sense of sight and the complete power of adapta- the furculum or clavicle ; the other large and strong, the 2 of it, at all distances, which birds possess. The cerebellum coracoid bone. The latter acts as a powerful fularum to the 1 spinal cord are both of large size. The latter presents ving, as well as a point of attachment to muscles. The purpose of maintaining warmth, and assisting in aerial pro- of the simple reptilian form. It varies from twice to eight, gression. Each feather is, as Paley truly observes, a mechanical times the length of the body. The first portion of the intestine, wonder. When fully formed, a feather is composed of a central immediately succeeding the stomach, is called the duodenum, cylinder or quill, by which it is attached to the skin ; a shaft, and is arranged in a characteristic loop-like fold, the interval which is the tapering continuation of the quill; and the vane being occupied by a gland called the pancreas, which is similar or beard which projects from each side of the shaft. The latter in structure to the salivary glands. The remaining portion is is composed of barbs and barbules. The feathers present some also more or less folded, but in an irregular manner, and finally variations in size and form in different parts of the body. They terminates in a short tube of greater calibre, called the large are variously coloured, and form the chief feature of ornamental intestine. In the mammalia, the large and small intestines are beauty of birds. The feathers are formed by the conversion of separated by a valvular fold of the mucous lining; in birds, the cells of the outer layer of the epidermis (skin) into horn-like however, there is no such arrangement. The point of terminamaterial.

tion of the ono and commencement of the other is marked by The Mandible or Bill consists of two portions, formed by the one or two pouches called cæca (Fig. III., 6), one on each side of elongated upper and lower maxillary bones, covered over with a the intestine. They vary in length from a simple offset, as in horny sheath, which serves the place of teeth. Besides being the Soland goose, to processes three feet in length, as in the a prehensile organ, the bill aids in the masticatory process to a grouse. The interior of the cæca of the ostrich is arranged in certain extent, and in some birds, e.g., the parrot, assists in a spiral manner. The cæca are wanting in many birds, as the climbing, thus acting as a third foot. It presents many inte-cormorant, wryneck, toucan, some vultures, etc. The large inresting modifications of size and shape, from the filamentous testine is short, straight, and destitute of folds, and terminates cone of the humming-bird to the huge bill of the toucan. The in the cloaca (Fig. III., 10). There is an appendage (Fig. III., food, and manner of obtaining it, peculiar to each species, 11) connected with the small intestine, the remains of the duct of determines the size, shape, and degree of hardness of the bill. communication between the yolk-bag and intestire in the chick. Thus it is strong and hook-like in those which tear their prey; Birds have no diaphragm or partition-muscle separating the short and conical in the grain-eaters ; probe-shaped in those thorax from the abdomen ; consequently, the liver, which is large which live principally on insects. In the ibis, the bill is curved and two-lobed, occupies a part of both cavities. It has appended down. In the jabiru (Fig. I., c.) it is bent up. It is dilated at to it a gall-bladder and a bile-duct. The latter opens into the the extremity in the spoonbill. Ducks, geese, etc., have their first part of the small intestine, and the fluid which it conducts bills flattened. In some birds it is dentated. Besides these, plays an important part in the digestive process. The spleen there are a variety of shapes, extremely interesting.

is small. The kidneys are large, and lodged along the upper The Tongue presents almost as many peculiarities as the part of the pelvis. From each kidney a tube--the ureter (Fig. mandible, and like it serves for the most part as an organ of III., 8)-passes downwards, terminating in the cloaca. Birds prehension. It is composed of muscles, covered with a horny have no urinary bladder, the urine being voided along with the sheath, and supported by one or two bony pieces (hyoid appara- excrements. tus), prolonged backwards behind the head (Fig. VIII.). This The Respiratory Apparatus.—This consists of an air-tube (the hyoid apparatus is very remarkable, especially in those birds trachea), with an upper and lower larynx, two lungs, and which dart the tongue rapidly at insects, as the woodpecker number of air-sacs variously disposed throughout the body. (Fig. VIII.). In the latter, the tongue is armed at its tip with The trachea, or wind-pipe, is a cylindrical tube, composed of sharp-pointed processes for transfixing insects. In the fieldfare a number of cartilaginous rings connected together by fibrous (Fig. II., 6.) the horny sheath of the tongue terminates in fine membranes. Its length accords with that of the neck of the filaments. In the snipe (a) it is long and slender. It is very bird. It is surmounted above, and also below, by a larynx. short in the kingfisher (d). The tongue of the goose (c) has The upper larynx is homologous in position, and in some respects projecting from its sides a number of recurvated spines. The in structure, with the mammalian larynx. But not in function. honey-eaters have the extremity of their tongue furnished with The lower one is the true larynx, from whence emanate the a tuft of horny, hair-like filaments. These peculiar shapes of sweet songs by which the feathered tribe relieve the monotonous the tongue are, like the mandibles, determined by the kind of stillness of country life. food, and the method of obtaining it. Beneath the tongue The rings which enter into the formation of the air-tube are there are a number of small cellular masses, called salivary not invariably of a uniform diameter, but sometimes present glands. These furnish & gummy-like Auid (saliva), which eccentric arrangements, as in the turkey, heron, eagle, eto, moistens the food. In the woodpeckers, and other insectivora, increasing in size from above downwards. Sometimes the the saliva is viscid, to enable them to entrap insects.

windpipe is found of a fusiform shape, thicker in the centre Alimentary Canal.—The first portion of the digestive tract, than at the extremities; or it may be convoluted at the root of extending from the mouth to the stomach, is called the gullet the neck. Sometimes one or more chamber-like dilatations ara Its length is proportionate with the bird's neck. It is usually found developed upon it. wide, and in some birds capable of great distension. At the The lower and true larynx is situated upon the inferior lower part of the neck it communicates with a receiving cavity extremity of the trachea, just before its bifurcation into the or crop (Fig. III.), where the food, after swallowing, remains bronchi. This complex apparatus will be best understood by a lodged for a time. A little below the crop there is another reference to Fig. VII., a, b (after Milne-Edwards). It may be dilatation, the proventriculus, or second stomach (Fig. III., 3), compared to a kind of osseous drum, the interior of which is and below this a third, the gizzard. The crop is a temporary divided inferiorly by a traversing beam of the same nature, reception-bag, the food lodging there until the gizzard is ready surmounted by a thin semi-lunar membrane (Fig. VII., 6, 2). to receive it. It is single, but of large size in the common This drum communicates inferiorly with two apertures of the fowl (Fig. III., 4). The pigeon has a double crop. In many glottis (rimo glottidis), formed by the termination of the bronchi, birds it is wanting, the food passing along the gullet to the true and each provided with two lips, or vocal cords. Finally, muscles, stomach at once, or, as in some birds that swallow whole fish, the whose numbers vary with the specios, extend between the difgullet is distended into a pouch-like cavity, serving the pur- ferent rings of which these parts are composed, and move them pose of a crop. The proventriculus (Fig. III., 3) may be smaller so as to stretch more or less strongly the membranes they supor larger than the gizzard. Its walls are thickly studded with port. In birds which do not modulate the sounds, the memsmall follicles called gastric glands, which pour out a fluid to branous septum is wanting. In those which do not sing there macerate the food, and to reduce it to a condition more readily are no muscles proper to the inferior larynx (Milne-Edwards). acted on by the gizzard. The gastric glands are variously The lungs are small and undivided. A subdivision of the arranged, and present some differences in size and shape. Some trachea (bronchus) enters the inner and lateral aspect of each of these are shown in Fig. IV., a, b, c, d, e.

lung, and after traversing the lang by smaller subdivisions The gizzard, composed of a dense aggregation of muscular (Fig. V., aa, bb), communicates on their inferior surface, by four fibres, is covered on its internal aspect by a dense skin-like memor more pairs of orifices, with the air-saos of the body. The brane, thus forming a powerful agent for the

mechanical reduc- latter communicate with the interior of the bones. Respiration tion of the food. Many birds further increase the power of reduc. is thus seen to be a very active and complicated process in birds, tion by swallowing pieces of flint, or other hard substances, and not confined to the lungs, but shared in by every part of the . The intestinal portion of the alimentary canal retains much body where air penetrates.

Circulation.-The temperature of the blood exceeds that of enlargements where the nerves emanate to be distributed to the any other vertebrates, ranging on an average from 100° to 1090 extremities. or 110°. In sea-birds, as the gull, the temperature is lower The Skeleton.—The skull of birds is made up of a number of than that of other birds, varying from 100° to 105°. In the bones, separate in the young bird, but which, speedily growing, common fowl it ranges from 107° to 110°. In the swallow it become inseparably blended together in the adult. The jaws, is said to be as high as 1111. The blood-corpuscles are for as already mentioned, are elongated, and both are movable. The the most part red, and nucleated.

lower one is connected to the cranial bones by the intervenThe heart is double, each one presiding over a separate tion of a second one called the tympanio or quadrate bone. system'; the right one over the pulmonary, the left one over | The skull is connected to the vertebral column by means of a VI.

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I. BEAKS OF (a) SHRIKE, (6) CROW, AND (c) JABIRU. II. TONGUES OF (a) SNIPE, (6) FIELDFARE, (c) GOOSE, AND (a) KINGFISHER. III. DIGES

TIVE CANAL OF COMMON Fowl. IV. GASTRIC GLANDS IN (a) EAGLE, (6) PIGEON, (c) Swan, (d) RHEA, AND (6) OSTRICH. V. DIAGRAM OF LOBULE OF BIRD'S LUNG. VI. FEMALE ORGANS OF FOWL AT BREEDING SEASON (OWEN). VII.a. INFERIOR LARYNX OF ROOK. VII.b.

VERTICAL SECTION OF INFERIOR LARYNX OF Rook. VIII. HEAD OF WOODPECKER (MILNE-EDWARDS). Refs. to Nos. in Figs.—III. 1, gullet ; 2, crop ; 3, proventriculus ; 4, gizzard ; 5, small intestine ; 6, cæca; 7, large intestine ; 8, 8, ureters;

9,9, oviducts; 10, cloaca ; 11, process for attachment of yolk-bag. V. a a, subdivisions of bronchus; 66, smaller subdivisions. VI. 1, ova, or yolks ; 2, vascular membrane of calyx; 3, zone, or stigma; 4, empty calyx; 5, infundibulum; 6, 6, oviduct; 7, oblique ridges of lining membrane of ovidact; 8, shell-forming dilatation; 9, egg exposed; 10, villi, containing follicles concerned in the secretion of shell; 11, convolutions of oviduct; 12, cloaca. VII.a, 1, trachea ; 2, drum formed by the lower end of trachea ; 3, middle ossicle ; 4, first ring of the bronchi; 5, bronchi; 6, proper muscles of the larynx; 7, depressor muscles of the trachea. VII.6. 1, inferior portion of the trachea. divided as regards the half ; 2, semi-lunar membrane ; 3, osseous cross-bearer ; 4, little rim formed by internal lip of the right glottis ; 5, inner surface of right bronchus, formed by a tympaniform membrane ; 6, portion of the cavity of the right bronchus exposed by a section

of part of this membrane. VIII. 1, hyoid apparatus ; 2, tongue. the general or systemic. The main object of the right system | single condyle. The vertebræ vary in number, the cervical is to remove from the blood carbonic acid, which results from ranging from ten to twenty. The dorsal, lumbar, and sacral the waste-tissue products, and replace it with oxygen.

vertebræ are generally found fused together and immovable. Nervous System. The brain of birds makes some little The coccygeal, which support the tail

, are movable. The advance towards the mammalian character. The cerebral sternum, or breast-bone, is large and expanded, and has prohemispheres are increased in size, and possess traces of conjecting in the

median line a keel-like ridge, to increase the survolutions. The ganglia which preside over the sense of taste face of attachment of the large elevator and depressor muscles are small

. The optic lobes are large, as might be anticipated of the wing. It has connected with it two bones ; one small, from the keen sense of sight and the complete power of adapta- the furculum or clavicle ; the other large and strong, the tion of it, at all distances, which birds possess. The cerebellum coracoid bone. The latter acts as a powerful fulorum to the and spinal cord are both of large size. The latter presents wing, as well as a point of attachment to muscles. The

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