. Elements of comparative anatomy. Anatomy, Comparative. GENERATIVE ORGANS OF VERTEBEATA. 619 in the former tliey are often broken up into several largo lobes, while in the latter they are distinguished by their length and by the diverticula which are found on them. The terminal portion also of the vas deferens often has a glandular structure. Besides the seminal ducts, the short terminal portion of which receives the vesiculas seininales, aud is known as the ductus ejacu- latorius, rudiments of the Mullerian ducts open into the urogenital sinus in many Mammals. They either consist of a single
. Elements of comparative anatomy. Anatomy, Comparative. GENERATIVE ORGANS OF VERTEBEATA. 619 in the former tliey are often broken up into several largo lobes, while in the latter they are distinguished by their length and by the diverticula which are found on them. The terminal portion also of the vas deferens often has a glandular structure. Besides the seminal ducts, the short terminal portion of which receives the vesiculas seininales, aud is known as the ductus ejacu- latorius, rudiments of the Mullerian ducts open into the urogenital sinus in many Mammals. They either consist of a single or of a paired diverticulum, which corresponds to a rudimentary sinus genitalis of the female, or, rather, to its vaginal portion, so that it is not very exact to call it a uterus masculinus. Part of it some- times forms a portion of the male genital sinus, for the seminal ducts open into it. These organs are largest in the Eodentia (Fig. 354, g), although, indeed, they are not altogether wanting in other forms; in Man they are represented by the prostatic vesicle. Lastly, the urogenital canal is provided with yet another set of glandular organs, the prostatic glands. These may be of a considerable size, and form paired lobate structures (Rodentia, Elephas, Insectivora) (Fig. 353, gl' gl"), or they are formed of a number of smaller tubes, which are connected by layers of smooth muscular fibres to a mass which is attached to the wall of the urogenital canal. By the further develop- ment of the musculature, which is found on these glands in other forms also, the prostate is converted into a circular body. B. § 456. In the lower divisions the efferent ducts of the urinary and generative apparatus unite with the terminal portion of the enteric canal to open into the cavity which has already (p. 562) been called the "cloaca;" but it is doubtful whether this should be regarded as the primitive condition, for we might take the arrangement which obtains in the Cyclosto
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectanatomycomparative
