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Show 1878.] GENERATIVE ORGANS OF HY/ENA CROCUTA. 423 Mr. Flower found no distinct uterus masculinus in Proteles; but as he refers to a median ridge on the floor of the urethra, in which he could detect a very minute aperture, the arrangement appears to be very similar to that described above in H. crocuta. In respect therefore of the form of the vesicula prostatica, H. crocuta agrees more closely with Proteles than with H. striata, differing from the latter inasmuch as the vesicula does not project beyond the urethral wall, and in the fact that it communicates with the canal of the same. According to Leuckart it is an extremely rare occurrence that the vasa deferentia open into the vesicula prostatica ; but this is certainly the case in H. crocuta. The penis of the Spotted Hyaena closely resembles that of H. striata and of Proteles, differing only from these in the absence of a conical body of cartilaginous consistence which has been described by Cuvier in the glans penis of the former and by Professor Flower in that of the latter. The glans penis in all of them is invested by small recurved spines. Comparison of the Male and Female Organs of H. crocuta.- When describing the female organs, I remarked that " the arrangement of these is such as to give them a great resemblance to those of the males in other species," and that, if we supposed the vesicula prostatica of the latter enlarged to the size of the female uterus, we should in the absence of a prostate gland, have an almost identical arrangement of the excretory passages of both sexes. The absence, as a matter of fact, of the prostate gland in tbe male H. crocuta makes the resemblance between the male and female organs of this species even greater than I anticipated. And here I may be permitted to observe that nowhere in the group of mammals is the truth of the conclusions at which embryologists have arrived respecting the homologies of the various parts of the sexual apparatus in the two sexes so beautifully shown as in the animal under consideration. Did any doubt remain regarding the similarity of plan upon which these are built up, it would be at once dispelled by an inspection of the sexual organs of Hycena crocuta. In both sexes there is a short urethra opening close to the mouth of the uterus, which organ, in accordance with functional requirements, is of large size in the female, but is reduced to a minimum in the male. In both there is a urinogenital canal extending from the junction of the urinary and sexual canals to the extremity of the penis or clitoris, according to sex ; and in both there are two Cowperian glands of large size opening into that canal close to the root of the penis or clitoris. A comparison of the internal genital organs of the two sexes proves conclusively that the lower part of the so-called prostatic, together with the membranous portion of the male urethra, are homologous with the commencement of the urino-genital canal of the female, which canal, in the majority of mammals, is so metamorphosed to form the vestibule, that its homologue in the other sex is by no means readily recognizable. This homology is further substantiated, in the animal we are considering, by the size and form of Cowper's glands, and the points of entrance of the ducts of these into the urino-genital canal in each sex. Lastly, the homology of the so- |