42 



CONTRIBUTIONS TO THE MORPHOLOGY AND 

 DEVELOPMENT OF THE FEMALE UROGENITAL 

 ORGANS IN THE MARSUPIALIA. 



I. 0\ THE Female Urogenital Organs op Perameles, with 

 AN Account of the Phknomena of Parturition. 



By Jas. p. Hill, B.Sc. (Edin.), F.L.S., Demonstrator of 

 Biology in the University of Sydney. 



(Plates i.-xii.) 



Introduction- 



The present paper, forming the first of a series of papers I hope 

 to contribute on the above subject, deals with the anatomy of the 

 female urogenital organs in the genus Perameles. These present 

 features of exceptional interest and importance, not only struc- 

 turally, but also in relation to the act of parturition, and form a 

 most excellent starting point from which to discuss the compara- 

 tive morphology of the urogenital organs in the Marsupialia. In 

 this present paper, howe\'er, I do not purpose entering into an 

 extended discussion of this subject, but content myself with 

 giving a fairly extended account of the adult structural condition 

 of the organs, together with an account of the main phenomena 

 connected with the act of parturition. The material at my dis- 

 posal has consisted of a large number of sets of the female genital 

 organs of either P. nasuta or P. ohesula. Doubtless a careful 

 comparison of the genital organs of these two species would reveal 

 the presence of minute differences between them, but such, if 

 present, may from the point of view of this research, be dis- 

 regarded. In the literature of the subject, I can find only two 

 references to the condition of the genital organs in Perameles. 

 The first is a short account by Owen (1, p. 683) of the organs in 

 /'. ohesula. His account is as follows : — " In Perameles ohesula 

 the uteri are wider in proportion to their length than in the Kan- 



