1902.] CAEPAL ORGAN IN HAPALEMUR GRISEUS. 161 



are simply intensified callous papillse. I see no i-eason to doubt 

 their histological similarity in HajKilemur , though I cannot from 

 my own obsei'vations upon the actual specimens state this with 

 absolute certainty. In this case, therefore, the male HajJolemur 

 griseus is not characterized by any structure peculiar to its sex, 

 but merely shows an exaggeration of the characters found in the 

 female, a constant state of afi"airs in the secondary sexual 

 characters of animals. If the elevations upon the carpal oi-gan of 

 the female were much increased, the characters of the male would 

 be produced ; and it will be remembered that a portion of the 

 tract of integument in the male has preserved, at least in one 

 specimen which I described, the characters of the integument in 

 the female. The drawing to which I have referred shows also 

 that the carpal vibrissfe are present in the female as well as in the 

 male. It is but rarely that these hairs are absent in one sex and 

 present in the other of a given species \ 



With regard to the external structure of the arm in this Lemur, 

 I may finally observe that the naked patch of thickened integument 

 is not absolutely devoid of ordinary hairs. In transverse sections 

 a few of these are apparent. Here again we have a less modified 

 state of affairs in the female than in the male. 



In the male Hapalemur griseits I described the naked-eye 

 characters only of a peculiar gland underlying the tract of modified 



Text-fiff. 34. 



\ p 



Palmar surface of hand and forearm oi HapaJemiir griseiis, ? . 

 The integument is reflected to show gland (G) ; other letters as in text-fig. 33. 



skin upon the arm. This gland was of a white colour and very con- 

 spicuous, lying immediately below the skin. I find that the female 

 animal has precisely the same kind of gland (text-fig. 34), occupying 

 the same position. It underlies, in fact, the callous integument. 



1 Beddard, '• Observations upon the Carpal Vibrissa in Mammals," P. Z. S. 1902, 

 vol. i. p. 127. 



Proc. Zool, Soc— 1902, Yol. II. No. XI. 11 



