186 Professor Owen's Reply 



and each uterus opens into a separate compartment of the sac; 

 and thus is obviated the evil that would have ensued from the 

 simultaneous entry of two tender embryos into one common 

 contractile cavity. But in those species of marsupials in 

 which but one ovum is developed at one pregnancy, two dis- 

 tinct cul-de-sacs are unnecessary, and the uteri open into one 

 common ccecal cavity. Now this latter is precisely the con- 

 dition of the female organs in the kangaroos, to which M. 

 Coste attributes the multiparous type of structure, in describ- 

 ing the median cul-de-sac as being divided by a 'cloison inter- 

 mediaire.' I suspect that here again M. Coste has deceived him- 

 self, by a hasty glance at my plate vi. in which an imperfect 

 or rudimental septum, such as usually exists in the kangaroo, 

 is represented. M. Coste would have escaped the double er- 

 ror of adducing what forms the distinctive peculiarity of the 

 female organs of the multiparous marsupials, as the type of 

 those parts in the whole order, and, — what makes the error an 

 absurdity, — the ascription of this peculiarity to the uniparous 

 kangaroo ; and he would also have been acquainted with 

 what I conceive to be an interesting physiological relation, 

 had he ever perused in the original, my Memoir of 1834.* 



It may be said that the subject of the structure of the ge- 

 nerative organs of the kangaroo, has little reference to the 

 question of the discovery of the allantois in this species : I 

 admit it. But it must be remembered that the irrelevant in- 

 troduction of this subject into the present discussion did not 

 originate with me ; and I now allude to it only to shew what 

 are the qualifications of the man who proposes, in his refuta- 

 tion of my claims to the discovery in question, to teach the 

 whole known history of the ovology of the kangaroo. 



Among the numerous topics with which the question of the 

 discovery of the allantois is involved by M. Coste, in this his- 

 tory, are some corrections of my nomenclature of the consti- 

 tuents of the ovum ; and he taunts me for retaining certain 

 opinions, as, for example, regarding the analogy and organized 

 nature of the chorion, which he considers to be obsolete. Thus 

 he conceives himself to have exploded from oology the term 

 chorion, as applied to the most exterior of the membranes of 

 the mammiferous ovum, and to have degraded it to asynonyme. 

 But M. Coste is little aware all the while, that the imperfect 



* The blunder into which M. Coste falls in his first step in the general 

 history, is the more ridiculous, as he proposes to restrict his observations to 

 the physiological relations of the parts in question. "Mais pour ne pas 

 donner a une question secondaire, plus de poids qu'elle n'en a reellement, 

 nous serons succinct dans notre description, et nous la ferons plutot sous le 

 point de vue physiologique que sous celui de Panatomie : " p. 4. 



