the Genera of Hapalidse. 257 



so far as I am aware, there is no evidence that this area 

 bt'conies bald even in extreme old age. The condition 

 presented by this species, indeed, lessens the value — small in 

 any case — of the characters upon which Seniucehus was based; 

 and if Elliot had not unconsciously evaded the diflSculty by 

 placing leucopus in a wrong genus, he would probably have 

 been puzzled in deciding whether it shonld be located under 

 Seiiiocehus or Cercopitliecus or Leontucehus^ in the sense in 

 which he used those terms, because the species is intermediate 

 between Seniocehus and the others, according to Elliot's 

 df Hnition of that genus. 



Elliot quoted Tamarin, Gr''^y> as a synonym of Seniocehus. 

 This is an unintelligible error, because 2'amarin, Gray, 

 included only mulas and ursulus, the two species to which 

 Elliot restricted the name Cercopithecus. Tamarin, there- 

 fore, should have figured amongst the synonyms of Cerco- 

 pithecus. Moreover, since Tamurin has line priority over 

 Seniocehus, the former should have been adopted by Elliot, 

 with Seniucehus as the synonym, if, as he stated, the two 

 names had been applied to the same group of species. 



Genus Hapale, lUig. 



CalKthrix, Erxl. Syst. Regu. Anini. 1777, p. 55; ty^e jacchus, Linn.* 

 Mcqjale, lllig. Prodr. Syst. Mamm. p. 71 (1811); iy^^ijacchus. 



This genus contains many species broadly resembling Mystax 

 in the structure of the hands and feet, and apparently also of 

 the ears, but differing from Mystax, as from the other genera 

 of the family, in the well-known modification of the anterior 

 mandibular teeth described by Gray and others ; the incisors 

 are abnormally long, and form a continuous or nearly con- 

 tinuous series with the canines, which they approximately 

 equal in height and thickness. This modification is accom- 

 panied by a more or less marked compression and recession 

 of the chin. Although these characters are subject to a 

 certain amount of specific and possibly individual variation, 

 I have seen no skulls of Hcqyale which could not be at once 

 identified as belonging to that genus. 



* I see no reason to interfere -with the synonymy of this genus as 

 puhlished by Elliot. T have only been able to examine in the fresh state 

 one species — namely, jacchiis, the common -n hite-eared marmozet, with 

 ■which the black-eared form, quoted as penicillatus and given f uU specific 

 status by Elliot, completely intergrades. Jacchus may be taken as the 

 type of Sctffoninus, Kerr, Hapale, Illi<^., Jacchus, Geoffr., Arctopithecus, 

 \'irey, Ouistitis, Burnett, and Liocephahts, Wagn. Generic synonyms 

 ^vith other type-species are : — Mico, Lesson, type aryentatvs ; Micodla, 

 Gray, type sericca { = chrysoleuca) ; Cebuella, Gray, ty^e pypiiceu. 



