which opens into a wide urethra about an inch from the end of the clitoris, the groove of which is continued from the urethra. The usual subordinate relations of urethral and vaginal canals are here reversed. The clitoris in Dasypus 6-cinctus is longer than in the 9-banded species, measuring nine lines in the unerect state: it is of a pointed form, covered with a leaden-coloured integument, and situated an inch anterior to the anus: the vulva is placed on an eminence. From this orifice the urogenital canal extends eight lines, receiving the vagina by a transverse semilunar slit, and being then continued for five lines further without any diminution of diameter, and terminating in the form of a cul-desac, into which the urethra opens by a very small orifice. In Das. Peba, the urogenital cavity is not separated by a corre sponding contraction from the urinary bladder, but is a more direct continuation of it. In this Armadillo the uterus is undivided; it expands to the fundus, which again contracts to a point, the oviducts being continued from the sides of the fundus: in Dasypus 6-cinctus the uterus is triangular, the fundus expanding into slightly produced angles, from which the oviducts are continued. These, in both species, wind round the peritoneal capsules of the ovaries, become tortuous, and terminate by fimbriate expanded openings directed toward the ovary, which was subelongate and smooth in both the dissected specimens.

In the Ai (Bradypus tridactylus) the uterus is like that of Dasypus 6-cinctus, the oviducts being continued from the angles of the fundus: between the uterus and vagina there is as little distinction; and the elongate common canal communicates (in the young Sloth) by two apertures with a short and wide urogenital passage. The ovaria are smooth elliptic bodies, with a greater proportion of stroma than in multiparous Lissencephala: the oviducts, commencing by fimbriate apertures upon the anterior edge of the capsule, pursue a serpentine course in that peritoneal fold to the fundus uteri. The ovarian ligaments are continued each along the margin of a peritoneal fold upward to the diaphragm, and downward to an oval parovarium,' or remnant of unusual size-of the Wolffian body': the unobliterated termination of its duct opens, as in most Lissencephala, on each side the urogenital passage, here very short. In the Unau (Bradypus didactylus) the rudiment of an uterine septum appears as a longitudinal ridge from the inner surface of the anterior wall in the unimpregnated state: in this species, also, the utero-vaginal canal communicates in the virgin animal by two distinct orifices with the short urogenital tract, the outlet of

which is common with the vent. The clitoris is short, and does not project beyond the cloacal aperture. In the great Anteater (Myrmecophaga jubata) the vulva and vent have likewise a common external cloacal outlet.

§ 387. In Cetacea.-The ovaria are narrow and elongate, with the surface frequently fissured so as to appear convoluted: the orifice of the pavilion' is rarely fimbriate, but the lining membrane is produced into numerous folds, which sometimes project like a short fringe. The uterus is bicorn' with a short body: the lining of the cornua' is longitudinally plicate: the os tincæ is prominent: the surface of the vagina has many complex transverse folds. The vulva is a longitudinal fissure, fig. 608, a, anterior to the vent, ib. b: its labia are composed of soft and yielding integument not loaded with oil: a short urogenital tract is marked off by the entry of the urethra upon a longitudinal ridge of the vagina: anterior to the urethra are two folds, like the labia minora,' between which is the clitoris: at the sides of the urogenital passage are the orifices of Malpighian canals.' In Bulanoptera the peritoneal fold forms a wide and shallow sac beneath the ovary the oviduct dilates at first, then contracts, and after a short wavy course is continued straight to the corresponding horn of the uterus. The lining membrane of this part is longitudinally plicate; the folds subside at the beginning of the corpus uteri,' but again reappear, and are continued upon broader transverse or circular productions of the lining. The third of these, progressively increasing in depth, represents the 'os tincæ:' just beyond this, at the beginning of the vagina, is a semicircular fold, also multiplicate longitudinally: it is followed by four other transverse folds progressively increasing in width: beyond these the longitudinal plicæ gradually subside. In Hyperoodon about ten oblong processes surround the entry of the oviduct into the uterine horn, into which they project: the uterine body presents a few large smooth ridges and obtuse processes. The 'os tincæ' is divided into five tubercles: about six inches intervene between these and the first transverse fold of the vagina: between these folds the membrane is produced into smaller wavy and longitudinal rugæ. In Delphinus delphis and in Phocæna the entry of the oviduct into the uterine horn is not defended by processes of the lining membrane. The longitudinal and transverse productions of the uterine and vaginal inner surfaces resemble those of the Whale. The larger folds of the vagina appear like a succession of ora tincæ.''

1 xx. vol. iv. p. 175.

§ 388. In Sirenia.- In both Halicore and Rhytina the vagina, fig. 544, o, is characterised by longitudinal rugæ: the body of the

544

uterus, c, is relatively longer than in Cetacea, and, in the young unimpregnated Dugong, is wavy: the cornua diverge at right angles, are more slender, and less arched: there is a well

Steller describes the clitoris as of a hard texture, an inch and a half long, situated at the anterior broader part of the vulva, which is eight inches anterior to the anus.

$389. In Proboscidia. In a half-grown female Elephant (Elephas Indicus, Cuv.), the ovaria are small oblong bodies, with an irregular tuberculated exterior and large proportion of stroma: the ovarian apertures of the oviducts are provided with numerous long and slender branched processes, like a loose tassel. Each tube makes a long bend upon itself around a deep and narrow ovarian capsule, and maintains a slightly tortuous course to the uterus. The body of the uterus is very short; the cornua are long and wide; their inner surface is broken by a few slight transverse puckerings on the concave side. The body of the uterus presents two large semilunar folds, and the os tincæ is represented by three similar successive and alternate folds, which form the boundary between the uterus and vagina: the latter is divided from the urogenital canal by a constriction, in which, viewed from the urogenital side, there appear three small apertures: the middle one leads to the vagina; the lateral ones to the mucous sinuses, called 'canals of Malpighi.' The internal surface of the vagina presents a few slight and irregular rugæ ; those of the urethro-sexual canal affect a more regular, and in some places a penniform, arrangement: the urethra terminates immediately beyond the constriction. The clitoris measures fifteen inches in length. The two crura are attached to the rami of the os pubis: they are of a dense cavernous texture, and are joined together to form the body of the clitoris: this is inclosed in a strong ligamentous capsule. After the junction of the crura the clitoris descends along the perineum, with its under

or posterior surface applied to the urogenital canal; two muscles, answering to the levatores penis in the male, converge and unite upon the upper or anterior part of the clitoris, and send their common tendon through a sheath to terminate near the glans: this is composed of a vascular corpus spongiosum.

§ 390. In Perissodactyla.-The ovaria, in Rhinoceros Indicus, are included within a large peritoneal sac, communicating with the general abdominal cavity: they are compact, oblong and subcompressed. The oviducts commence by wide orifices, having a richly fimbriated margin: their diameter at the expanded end equals two-thirds of an inch, but they gradually diminish in size as they pass in a slightly tortuous course along the parietes of the ovarian capsule towards the uterus: just before they enter the cornu their diameter does not exceed one-third of a line. They terminate in the extremity of the cornu upon a valvular protuberance about the size of a pea, which is divided into four or five processes. The cornua uteri' are each seventeen inches in length: the corpus uteri' only an inch and a half. The cornua are occupied by close-set longitudinal folds: the inner surface of the corpus is smooth. The vagina, about sixteen inches in length, is divided by a constriction from the urogenital tract, which is three inches long. The upper or uterine third of the vagina is occupied by broad transverse folds, the lowest of which is most extensive. About an inch above this fold, or nearer the uterus, a second and smaller fold is formed, which also descends from the upper and lateral parietes of the vagina, but passes across in an oblique direction: then follow in quick succession a series of shorter but equally broad semilunar folds, which become alternate in their relative position as they approach the uterus, so as to cause the cavity of the vagina to assume a spiral course: as these valvular folds also assume a thicker, softer, and more vascular texture, it is by no means easy to determine where the vagina ends or the uterus begins.' The structure resembles that in the Tenrec and some other Lissencephala. The urethra opens into the urogenital passage just beyond the vaginal constriction. The lateral apertures of the Malpighian canals' are about an inch and a half from the vulva. These canals expand, and then divide and subdivide, terminating in blind ends near the beginning of the vagina. The preputium clitoridis' and urogenital canal open externally by distinct but approximate narrow elongate orifices: the vulva opens about five inches from the vent.

2

6

In the Tapir the ovaria are small subcompressed oval bodies, in a widely open peritoneal pouch; the oviducts have a tortuous course along the pouch near its margin to the uterine horns, which are long, and longitudinally multiplicate within: the body of the uterus is but two inches long, the 'os tincæ' not very prominent the vagina is long; a constriction divides it from the urogenital passage, which is short. The clitoris and Malpighian canals resemble those of the Rhinoceros.

In the Mare the ovaries, of an elongate reniform figure, are inclosed and concealed in large peritoneal sacculi, fig. 574, z, to the mouths of which the fimbriated extremities of the oviducts are attached. The inner surface of the pavilions are characterised by numerous narrow, close-set, minutely plicated laminæ. The oviducts have a wavy course to the horns of the uterus, which are a little longer than the body or common cavity; short oblique wavy folds of the lining membrane, much developed in the impregnated state, fig. 575, t, project into the interior: a few similar folds are present in the body of the uterus, together with others which are broader and disposed more longitudinally at the cervix. The os uteri, ib. 7, is denoted by the sphincteric thickening of the muscular coat and the contraction of the canal; but there is little or no valvular projection into the vagina. Of this canal, k, the inner surface is increased by numerous irregular longitudinal folds: a constriction defines the vagina from the urogenital passage, ib. d; the urethra, ib. e, opens near the constriction, behind a rugous prominence or flap, ib. f. The orifices of many follicles are dispersed over the comparatively smooth surface of the urogenital passage. The trilobate glans clitoridis,' ib. a, projects from its preputium close to the anterior margin of the vulva. It is provided with erectores' muscles and a plexus

545

retiformis': the sphincter of the urogenital passage is very powerful. In the Filly the communication of the vagina with the urogenital canal is divided by a longitudinal septum or 'hymen.' The Zebra and Ass closely agree with the Mare in the structure of the female organs.

§ 391. In Artiodactyla. - The ovaria of the Sow, fig. 545, are large oblong bodies with an irregular and tuberculate surface: when the ovisacs enlarge, the stroma is scanty in proportion. Each ovarium is inclosed within a peritoneal sac, near the aperture of