id 
790 
Genus.—Aulacddus. 
Teeth.—Incisors broad and short, brown in front, three 
furrows in those of the upper jaw. Molars with four folds of 
enamel. 
Limbs.—Fore-feet with thumb and outer toe short. 
feet with four toes. 
Tail.—Rather short, slightly covered with hair. 
Fur.—Composed of flattened and grooved hair, or grooved 
spines. 
Habitat.—Southern Africa. 
Hind- | 
Family.—HYSstRiciD&. 
Teeth.—Incisors smooth and large; molars with waving | 
strips of enamel, always 
4-4 
Limbs.—Fore-feet with four toes, a wart instead of the 
thumb-joint. ; 
Fur.—None, being replaced by strong and sharp spines, 
Sub-family—Hystricina. 
Teeth.—Molars with undivided roots, set deeply in the 
bone ; third molar placed under the anterior margin of the 
orbit. 
Limbs.—Feet with soles smooth, but grooved. 
Genus.—Hystrix. 
Limbs.—Hind-feet with five toes. 
Tail.—Not prehensile. | 
Habitat.— Parts of Europe, Africa, and Asia. 
Atherura is included in this genus. 
Sub-family.—Cercolabina. | 
Teeth.—Molars with short, divided roots, set shallow in 
the bone. First molar placed under margin of orbit. 
Limbs.—Feet with warty soles. 
Genus.—Erethizon. 
Tail.—Short and spined. 
Limbs. —Hind-feet with five toes. 
Fur.—Long hair, interspersed with short, sharp spines. 
Habitat. —Canada. 
Genus.—Cercélabes. 
Tail.—Long and prehensile. 
Limbs.—Hind-feet with four toes. 
Habitat.—Brazils. 
Sub-family.—Subunguldta. 
Teeth.—-Molars complex. 
Limbs.—Fore-feet with four or five toes, hind-feet with 
three or four, Claws large and keeled above. 
Genus.—Dasy procta. 
Head.—Lips cloven. 
Limbs.—Fore-feet with four toes and a wart for the 
thumb ; hind with three toes. 
Tail.—Represented by a small, naked tubercle. 
Fur.—Hair long on hind-quarters. 
Habitat.—Brazils. 
Genus.—Ceelégenys. 
| 
Head.—Lip cloven. 
Great development of zygoma, lined 
with a fold of skin. 
Cheek-pouches, 
COMPENDIUM OF GENERIC DISTINCTIONS, 
Limbs.—Fore-feet with four toes and nailed wart for 
thumb. Hind-feet with three toes. 
Tail.—Very short. 
Habitat.—Tropical America. 
Genus.—Hydrocheerus. 
Teeth.—Slight longitudinal groove on upper incisors. 
Molars without roots. 
Head.—Thick, lips not cleft. 
Limbs.—Feet partially webbed. Fore-feet with four toes, 
hinder with three. 
Tail.—None. 
Habitat.—Tropical America. 
Genus. —Cavia. 
Teeth,—Incisors smooth. Molars without roots, and cu- 
riously laminated. 
Head.—Ears short and rounded. 
Limbs.—Feet cloven ; fore-feet with four toes, hinder with 
three ; feet short. 
Tail.—None. 
Habitat.—Brazils, 
Family.—LEPORID&. 
Teeth, —Four incisors in upper jaw, a pair of these teeth 
being placed behind the two usual incisors. Molars without 
roots, formed of two lamin. 
Limbs.—Fore-feet with five toes, hinder with four; soles 
hairy. 
Tail.—Short, or absent. 
Genus.—Lepus. 
oo 229) 99 A geo ee 
Teeth. —I. [—, P. =), M, 5 = 26. 
Head.—Ears long. 
Limbs.—Hind-legs longer than fore-limbs. 
Tail.—Short, and curved upward. 
Habitat.—Europe, Asia, Africa, and America. 
Family.—JERBOIDR. 
Limbs.—Fore-feet short. Hind-feet long, and formed for 
leaping. 
Tail.—Long, and thickly haired. 
Sub-family.—Chinchillina, 
Teeth.—Incisors smooth. 
Molars rootless, and composed 
of narrow laminze. 
Genus.—Chinchilla. 
44 
AT —M., —— y in in each, 
eeth.—_M. ’ three laminz in each 
Head.—Ears large, rounded, and scantily haired; whisker 
hairs very long. 
Limbs.—Fore-feet with five toes, hind with four. 
Habitat.—Peru. 
Genus.—Lagotis, 
Head.—Ears long, like those of the hare. 
Limbs. —Fore-feet with four toes. 
Habitat.— Peru. 
Sub-family.—Dipina. 
Teeth.—Molars with roots, and complex. 
