100 
MAMMALIA. 
in each jaw with very profound radicles towards the summit, 
composed of alternate folds, two on each side, extend to the 
middle of the teeth; the incisors in the upper jaw slightly 
rounded, in the inferior jaw obliquely truncate; tail hairy; feet 
simple; fore feet four-toed, with the rudiment of a fifth toe 
having a nail; hind feet five-toed. 
Sigmadon hispidum. —The Prickly Sigmadon. 
Zoological Journal, vol. II. plate X. fig. 5, 6, 7, 8. 
Head thick; snout elongated; eyes and ears large, the latter 
round, slightly clothed with hair; tail nearly as long as the body; 
fore legs short; hind feet large and strong; lateral toes very 
short; claws stout; upper parts and head pale dirty ochre 
yellow, mixed with black ; lower parts ash-coloured; hair of the 
upper parts and sides long, plentiful, and coarse. Length from 
the tip of the snout to the tail six inches ; tail four inches. In¬ 
habits the banks of the river St John in East Florida. 
Genus 7.—Lemmus. — Cuvier. 
Generic Character. —Incisors |, no canines, grinders ; to¬ 
tal 16. Grinders with a flat crown and angular plates of ena¬ 
mel ; ears very short; fore feet in some species have five and 
in others four toes, with nails on all of them fitted for digging; 
tail short, covered with hair. 
Lemmus Norvegicus. — The Lemming, or Lapland Marmot. 
Plate XVIII. fig. 9. 
Fur reddish-yellow, or tawny, clouded, or irregularly spotted 
with black ; fore feet with five toes; thumb nail large and strong. 
Length of the body five to six inches; tail about half an inch. 
Inhabits Norway and Lapland. 
There is a variety a fourth less in size, with a light band pass¬ 
ing from the nose to the ear. 
Genus 8.—Echimys. — Geojfroy. 
Generic Character. — Incisory teeth |, no canines, grinders £-4. 
