126 
NATURAL HISTORY. 
[n. ZOOL. GAL. 
fur, the latter indeed very rigid, and the remainder have flat channelled 
grooved spines intermixed with their fur, as Loncheres, Nelomys , 
( Echimys , Cer corny s, F. Cuv.) an & Dactylomys. 
The family of Porcupines (Histriclcle) have the tongue and body 
covered with cylindrical spines or bristly hair; their clavicles are in¬ 
complete or quite wanting; the grinders are four in each jaw. Some 
are covered with spines and have compound rooted grinders, as the 
Histricina, which have a short tail with pedicelled spines, which rattle 
as the animal shakes ; they live on herbs. Others have a more or less 
elongated tail, and live on trees, eating the leaves, as the Erethyzon, which 
has a truncated tail, and the Cercolabes and Sphigurus, w T hich have a 
prehensile one. The remainder of the family have more or less rigid 
hair; they have none or a very short tail, and long hoof-like claws. 
Some, as Dasyproctina, are omnivorous, and have complicated grinders. 
Dasiprocta has no cheek pouch, and Ccelogenus has large cheek 
pouches under the zygomatic arch, opening on the side of the cheek. 
Others have composite rootless grinders, living on herbs near water, 
as the Hydrochcerina , which have harsh bristly fur, large hoof-like 
claws, and the hinder grinder formed of many plates; and the Ca - 
viina, which have a soft fur and smaller claws, and each of the grinders 
formed of two plates, as the Cavies ( Cavia ) with a short head and large 
teeth, and Moko ( Kerodon ) with an elongated head. 
The other Glires have soft nearly equal fur, and no or a hairy tail. 
The family of Hares ( Leporille) have two small teeth behind the 
upper cutting teeth, five rootless grinders in each jaw, each formed of 
two plates. The infra-orbital foramen is small, the bones on the sides 
of the skull are pierced; the ears and eyes are large, the tongue hairy, 
the clavicles are incomplete, the fore feet are generally weak, tail is 
short and hairy. The Hares ( Lepus ) have the hinder grinder smallest; 
the Rock Hares ( Lagomys ) the front grinder smallest. 
The family of Jerboas (Jerbolcle) have only two cutting teeth in 
each jaw; like most of the Glires, their eyes are large and prominent, 
their tail is long, hairy, and used in leaping or walking; therhind feet 
are much the longest, and the fore feet short and often used as hands ; 
their clavicles are distinct. Some have compound or rootless grinders, 
their tail is long and hairy, often flattened; as the tribe of Pedestes 
(Pedestina, Case ) of Africa, which have four grinders in each jaw 
with a single fold on one side of the crown ; the hind legs are very 
long, and the tail elongated. The tribe of Chinchilla ( ChinchiUina), 
which is peculiar to South America, has four grinders in each jaw, 
each formed of two or three parallel plates, the legs are more pro¬ 
portionate, the ears large, and the tail moderate, covered with long 
hair. The remaining genera have rooted simple grinders. The tribe 
of Jerboas {Dipina ) with very long hinder legs and long tails, have four 
grinders in the upper and three in the lower jaw, with irregularly lobed 
grooves; the first hinder grinder is very small. Some from North Africa 
and Asia have the end of the tail tufted, as Dipus , Alactaga , Iaculus. 
Some from America have the tail very long, slender, tapering, and 
covered with short slightly rigid hair {Memories'). Others have the 
limbs much more proportionate and equally strong. The tribe of 
Dormice {Myoxina) have four grinders in each jaw, the front 
thumb wart-like, the frontal bone contracted without any post-orbital 
