280 



Prof. Sir Wm. Turner. 



[June 7, 



the head was near the Fallopian tnbe belonging to the more dilated 

 of the two uterine cornua. In three specimens of Lemur rufipes 

 described in my previous memoir, the head was in proximity to the 

 os, and the caudal end of the foetus was in the more dilated horn. 

 It would appear, therefore, that in the Lemurs, either the head or 

 breech may be the part of the animal first to be born. 



The examination of the gravid uterus of Lemur xantlwmystax 

 confirms, therefore, the conclusions to which both Alphonse Milne 

 Edwards* and I had arrived independently in our previous investiga- 

 tions, that the placenta in this important group of animals is diffused 

 and non-deciduate, and that the sac of the allantois is large and 

 persistent up to the time of parturition. In these important respects, 

 therefore, the Lemurs are, in their placental characters, as far 

 removed from man and apes as it is possible for them to be. 



Although I am not disposed to attach too much weight to the 

 placenta as furnishing a dominant character for purposes of classifica- 

 tion, yet I cannot but think that animals which are megallantoid, 

 non-deciduate, and with the villi diffused generally over the surface 

 of the chorion, ought no longer to be associated in the same order 

 with animals in which, as in the apes, the sac of the allantois early 

 disappears, and the villi are concentrated into a special placental area, 

 in which the foetal and maternal structures are so intermingled that 

 the placenta is highly deciduate. Hence I am of opinion that the 

 Lemurs ought to be grouped apart from the Apes in a special order, 

 which may be named either with Alphonse Milne Edwards Lemnria, 

 or with Victor Carus and others Prosimii. 



Addendum. — June 2. 



After the foetus had been mounted for preservation in spirit, deli- 

 cate flakes of a translucent cuticuiar-looking membrane were seen 

 partially to float off from the surface of the abdomen and from the 

 ventral surface of the limbs. In the groins and axillee the membrane 

 was very distinct, and formed an almost complete covering for the 

 surface of the limbs external to the hairs, which, though of some 

 length, were few in number, and scattered over the surface of the 

 skin. On the dorsal aspect of the foetus, both on the head, trunk, and 

 limbs, where the hairs were longer and closely set together, the flakes 

 were much more fragmentary and over considerable areas were 

 absent. The appearance presented was such as to lead to the impres- 

 sion that flakes of a cuticular membrane, subjacent to which the hairs 

 had been developed, were in process of being shed. 



* " Histoire Naturelle des Mammiferes de Madagascar," forming vol. 6, chap, ix, 

 of Grandidier's ' Histoire de Madagascar.' 



