68 



occiput. The pterygoid bones much-swollen, very thin, paper-like. 

 The lower jaw with a broad square truncated process in front between 

 the teeth, the sides converging, with the outer edge reflexed ; the angle 

 broad, acute, slightly produced beyond the back edge of the condyles. 

 Teeth large, broad, the lower front one oblong, transverse : the lower 

 process of the zygoma broad, flat, dilated. 



The skull is easily known from the next by being much wider in 

 all its parts compared with its length ; this is especially visible at the 

 occipital ridge and the palate, and on the under side of the lower jaw. 



The Sloth figured by Edwards (Gleanings, t. 310) is from a badly- 

 preserved specimen in the collection of Lord Peters, brought from 

 Honduras. It appears to belong to this species, being the only one 

 having long hair on the neck, but the black colour of this crest is not 

 mentioned in the description. 



Bradijpus tridactylus, Linnaeus, was first described by that author 

 in the Amcenitates Acad. i. 487, but the description is so slight that it 

 is not possible to determine with certainty the specimen for which it 

 is intended, the only specific character being the following : "facie vero 

 pilis Jlavis vestitum; gulaflava, totum corpus ursorum instar, pilis 

 longis et asperioribus vestitur colore exfusco sive griseo et albo vari- 

 ante." In the Mus. Adolph. Fred. p. 4, Lmnseus refers to this de- 

 scription. The mixed colours of the first description and the habitat 

 Surinam best agree with this species. 



Gmelin merely described this species as " Corpus pilosissimum gri- 

 seum, fades nuda, gulaflava." 



Browne (Jamaica) mentions it as an animal which is sometimes 

 brought from the mainland to Jamaica (not as a native of the 

 island) ; his name at once shows that it must belong to this species. 



The skull above described was taken from the skin of a specimen 

 in the British Museum. We have also a skeleton of a second speci- 

 men, which was received from M. Becker under the name of Brady- 

 pus torquatus, from Brazil. It is the skull of this skeleton (it being 

 more perfect than the former) that is figured in tab. X. f. 1. a, b, c. 



2. Bradypxjs affinis. 



{Skull, Mammalia, PI. X. f. 2. a, b, c.) 



Fur unknown. 



The forehead of the skull rather convex, with a slight convexity 

 over the orbits and a higher convexity over the front part of the tem- 

 ples. The occipital ridge very concave and rather narrow. The ptery- 

 goid bones rather swollen, rather compressed on the sides, and mode- 

 rately thick. The lower jaw with a broad, gradually tapering, trun- 

 cated process in front between the teeth ; the sides rather curved, 

 simple-edged beneath ; the angle broad, acute, slightly produced 

 beyond the back edges of the condyles. The lower process of the 

 zygoma slender, tapering. Teeth moderate, the lower front one much- 

 compressed, transverse, linear. 



Hab. Tropical America. 



The skeleton from which this skull has been described and figured 

 was received by the British Museum from M. Brandt, under the name 

 of Bradypus torquatus, from Brazil. 



