The =corpora cavernosa penis= (Fig. 111, _j_). Each is a cylindrical sheath of dense fibrous tissue within which are trabeculæ separating blood-sinuses. Each corpus cavernosum is attached by the one pointed end to the caudal border of the ramus of the ischium near the symphysis. From their attachments the corpora cavernosa approach one another, forming the =crura= of the penis. They become closely united by their medial surfaces and pass thus to the free end of the penis where their somewhat pointed distal ends are imbedded in the glans (_m_). A groove is left between the corpora cavernosa on the dorsum of the penis, and there is a second groove on the ventral side. In the latter groove lies the urethra. The =corpus cavernosum urethræ= is the spongy portion of the urethra which lies in the groove on the ventral surface of the penis, between the corpora cavernosa penis. It becomes greatly enlarged at the distal end of the penis, forming the =glans= (_m_). A small bone (=os penis=) is imbedded in the distal end of the penis. B. FEMALE GENITAL ORGANS (Fig. 112).--The urinal organs of the female are like those of the male. The neck (_k_) of the bladder is, however, much longer, extending almost to the border of the ischiatic ramus. The urethra is consequently short. The genital organs consist of the =ovaries= (_c_) (the organs which produce the eggs), the =oviducts= or =uterine tubes= (_e_) (=Fallopian tubes=), which receive the eggs from the ovaries; a bifid =uterus= (_f_ and _i_) in which the ova undergo their development, and a =vagina= (_m_) which leads from the uterus to its junction with the neck of the bladder. The neck of the bladder (_k_) unites with the vagina to form the =urogenital sinus= (_n_) which is very short, leads to the external opening, and is comparable to the male urethra. Ventrad of the external orifice of the urogenital sinus is the =clitoris=, a rudimentary structure homologous with the penis of the male. _The Ovaries_ (_c_).--The ovaries lie in the abdominal cavity in the same longitudinal line with the kidneys and a short distance caudad of them. Each is an ovoid body about one centimeter long and one-third to one-half as broad. On its surface are numerous whitish projecting vesicles, the larger of which show clear centres. They are the =Graafian follicles= (best seen in section), which contain the eggs. There may be present one or more elevations of the size of the largest Graafian follicles, but of a bright red or brown color. They are the =corpora lutea= (sing. corpus luteum),--Graafian follicles from which the eggs have been discharged.