1902.] OARPAL VIBRISS.E IN MAMMALS. 129 



character. Broadly speaking, it may be stated that this sense- 

 organ, as we may in the meantime assume it to be, characterizes 

 the Lemurs, Rodents, Garnivora, and Marsupials, and that it is 

 absent in the Ungulates (with the exception of Hyrax) and in 

 the Primates (excluding the Lemurs). The Bats I have not yet 

 studied from this point of view. Of the Insectivoi-a I am un- 

 willing to speak, as I have examined only Centetes and Erinaceus, 

 which certainly had not this tuft of hairs. 



As to the Edentata, the representative of this carpal tuft of 

 vibrlssae does appear to exist at least in the Armadillo, Dasyjyus 

 villosus, as the accompanying figure shows (text-fig. 17, p. 128). 

 But the hairs of that mammal are so coarse that there is but little 

 difference in size and general appearance between the tuft which 

 I compare to those of such an animal as Petaurus scmreus (text- 

 fig. 18, p. 130) and the general hairs of the body. The Sloth 

 {Braiypus tridactylus) has not any traces that I could discover of 

 this " organ." As to other Edentates I have no information to 

 ofi^er, except concerning Manis, where I have found no traces of 

 these hairs. 



Considered broadly, therefore, this carpal tuft of vibrissse is of 

 some little use for classificatory purposes, apart from its absence in 

 the Ungulates, where it might well be supposed to be deficient on 

 account of the lack of facilities for use. The most salient featui-e 

 as to its absence or presence is its nearly universal existence 

 in the Lemurs, and the absolutely universal absence (as far as I 

 have ascertained) in the Monkeys. These two divisions of the 

 Primates, as they are most commonly considered to be, have 

 been brought nearer to each other by recent researches upon 

 certain extinct forms such as Nesojnthecus ^, and by investigations 

 upon the placenta of Tarsms, which has been showoi to be ape- 

 like and even human in its characters '". It is not, therefore, 

 without interest to be able to bring forward a character which 

 seems to absolutely distinguish these two divisions of the Pri- 

 mates. Furthermore, it is not a character which has an obvious 

 relation to ways of life : if the tuft of vibrissa3 is useful to the 

 Lemurs, it would seem to be equally useful to the Monkeys, many 

 of whom use their hands as climbing- and grasping-organs in the 

 same way. And I can at least assert, that while the majority of 

 the Lemurs (excluding the Potto and the Loris) which I have 

 examined possess this tuft, the large number of Monkeys, both 

 of the Old and New Worlds, which have passed through my 

 hands do not possess it. 



As to the Marsvipials, the genus Macropus, so far as my present 

 investigations go, stands alone in that the wrist is not provided 

 with this tuft of vibrissfe. I have examined both adults and 

 quite newly born individuals of several species. In the naked 

 new-born young of Marsupials this tuft of vibrissas is exceedingly 



1 Forsyth Major, P. Z. S. 1899, p. 987. 



- See, for a survey of the position of Tarsms, Earlo, Amer. Naturalist, xxxi. p. 569. 



Proc. Zool. Soc— 1902, Yol. L Xo. IX. 9 



