448 DR. J. E. GRAY ON THE BRADYPODID.E. [May 2, 



b. The male with a small patch of soft whitz hair on the back. 

 8. Arctopithecus flaccidus. (Plate XXXVII.) 



Fur elongate, flaccid, grey, very indistinctly marbled with white ; 

 under-fur very abundant, white and black in spots and blotches. Skull 

 with a short broad nose. Lower jaw thick, short, high, thickened 

 in front and very blunt ; angle of lower jaw produced beyond the 

 back edge of the condyle, rather broad (P. Z. S. 1849, t. xi. f. 1 a). 



Bradypus tridactylusl, Prince Maximilian, Abbildungen. Female 

 and young. 



Bradypus ai, Wagler, Isis, 1831, p. 610 ? 



Bradypus pallidus, Wagner, Suppl. iv. p. 143? 



Arctopithecus flaccidus, Gray, P. Z. S. 1 849, p. 72, t. xi. f. 1 (skull) ; 

 Cat. Edentata, p. 365. 



Hab. Venezuela {Dyson); Parti (J. P. G. Smith). 



The figure of the skull, t. xi. f. 1, in the P. Z. S. 1849, represents 

 the angle of the lower jaw as slender and acute ; but the underside of 

 the angle represented has been broken off, and the smaller figure, 

 t. xi. f. la, represents the true form of this part. There is a ske- 

 leton in the Museum which I believe belongs to this species. 



The two specimens in the Museum are probably males ; but we 

 have no means of determining the fact. They are both peculiar for 

 the long, soft, flaccid hair, of a dull whitish-grey colour, without any 

 indication of white or black markings, being only slightly grizzled 

 by some of the hairs being whiter than the rest. There is a very 

 abundant, rather long, very soft, blackish brown under-fur, and only 

 a slight indication of a broad, short, blackish dorsal streak seen at 

 the base of a deep concavity in the fur between the shoulders. This 

 streak is much more visible in the specimen from Venezuela than in 

 the smaller one brought by my son-in-law from Para. 



Prince Maximilian of Neuwied, in his ' Abbildungen,' has given a 

 beautiful figure of a female Bradypus tridactylus, and its young one 

 on its back, which is probably intended for A. flaccidus ; for it has 

 the long flaccid hair of this division ; and he says the female has the 

 longitudinal black streak in the woolly hair, and that the male has 

 a longitudinal white line on each side of the back. Does he mean 

 by this the small white central spot of soft hair between the shoulders, 

 which is characteristic of this species ? 



Wagner refers this figure to his Bradypus pallidus ; and the spe- 

 cific character may be only a travesty of Prince Maximilian's de- 

 scription, where he changes the white longitudinal streak into the 

 back being longitudinally white-spotted, observing there is no orange 

 fulvous dorsal spot, not thinking that the white stripes replace this 

 patch in the other species — that is to say, if the figure represents 

 A. flaccidus, which I think is probable ; and it is the best published 

 figure of the genus. 



V Ai, Cuvier, Oss. Foss. vol. v. t. vi. & vii. (skeleton and skull). 

 A. problematicus, Gray, P. Z. S. 1849, p. 73, t. xi. f. 5. 

 Bradypus problematicus, Gerrard, Cat. Bones Mam. p. 290. 



