670 CLASS XVII. 



World, but all, witli tlie exception of a single species, in warm 

 countries. These animals possess clavicles, wliicli, however, are not 

 quite perfect, being attached to the sternum only and not to the 

 scapula; they have commonly fourteen ribs; the length of the tail 

 and the number of its component vertebrae is very various. The 

 skeleton presents, in all instances, five digits on the fore and hind 

 limbs, of which however the imaermost is short or impei'fect. They 

 feed on young shoots of trees, bark and fruits. 



Comp. F. CuviER Examen des especes du genre Pore-epic, &c., Mem. dii 

 Mus.'ix. 1S22, pp. 413—437, with fig.; — J. F. Bkandt Mammalium 

 exoticorum novormn vel viinus recte coynitorum Descriptiones et Icones, 

 Petropoli, 1835, pp. 21 — 89. 



Tribe I. Philodendrce Brandt. Head short, truncate anteriorly. 

 Molar teeth with roots distinctly divided, somewhat short, sinking 

 into the jaws not very deeply. Orbital process situated over the 

 first molar tooth. Soles of feet warty. (Species American.) 



Cercolahes Beandt {SpMggunis and Synctheres F. Cuv.). Tail 

 long, prehensile, thinly haired towards the tip, annulate. Hind feet 

 with only four unguiculate toes. 



Sp. Cercolahes prehensilis, Hystrix prehensilis L., Buff. Suppl. vii. PI. 78, 

 Cuv. R. Ani., ed. ill., Mammif. PI. 65, fig. i ; Brasil, Surinam, with 

 strong sjaines, black at the base, white at the point ; — Cercolahes insidiosus 

 Brandt, Hystrix insidiosa Lichtenst., Spkiggurus viUosus F. Cuv., Max. 

 Ahh. zur Naturgesch. Lief. 11., Schreb. Sdugth. Tab. 168 a, Gubr. Iconogr., 

 Mammif. PI. 30, fig. 2 ; smaller ; the spines concealed under the long hair 

 of the back. These species live in trees in South America, feed on fruits, 

 and are very slow in their movements ; they mostly rest by day. (See also 

 BuRMEiSTER iS/s<. Uebersiclit der Thieve BrasHiens, i. Berlin, 1854, s. 216 

 —225.) 



Note. — Sub-genus Chcetomys Gray ^, Plectroclioerus Pictet (is it a distinct 

 genus?). Spines flexile on the head and fore part of the back, passing into 

 setae on the rest of the back. Skull differs from that of the rest of the 

 Aculecda by the orbit nearly closed posteriorly and the broad zygoma. Sp. 

 Cercol. sid)spinosus Wagn., Hystrix suhspinosa Lichtenst., Kuhl. Hab. 

 in the North of Brasil. 



EretMzon F. Cuv. Tail short. Hind feet with five unguicu- 

 late toes. Spines concealed amongst the long hair. 



Sp. EretJdzon dorsatum Cuv., Hystrix dorsata L., Buff. xn. PI. 55, Richards. 

 Faun. bor. Am. i. pp. 214 — 216; in North America from 37° to 67° N.L. ; 

 the individuals of this species are very variously coloured ; some yellow- 

 brown, others black. 



^ Proceed, of the Zool. Soc. 1843, pp. 21, 22. 



