570 
U. S. P. R. R. EXP. AND SURVEYS-ZOOLOGY-GENERAL REPORT. 
muffle is entirely hairy. There are hut four fingers on the fore feet, without any rudiment of a 
thumb; the palms are sub-quadrate, longer than broad; flat, and closely granular—tuberculate. 
They are divided by a transverse fissure from the fingers, which are likewise naked beneath. 
The soles are plantigrade, very broad ; the surface of the sole, like that of the palm, plane, 
without any prominent tubercles, hut covered with a pavement of depressed granulations, re¬ 
sembling very much that of a hear in general appearance; it is about 1^ inch wide, by 2^ long. 
This is separated by a furrow from the toes, the bases of which are hairy beneath, hut naked 
towards the halls ; even these appear hairy from the overlapping of the long bristles of the 
side. The first toe is very short, the remaining four appear of nearly equal length. The 
claws of all the feet are very long, nearly equal ; the posterior stoutest. The tail is short, 
very thick, and much depressed. 
The animal is covered on the upper parts and sides with a dense growth of short spines. 
These become thinner and thinner, till on the lower part of the sides they pass through 
thickened spinous hairs, to coarse bristly hairs. On the middle of the belly there are no spines 
at all, nor on the lower part of the limbs. The muzzle is also free from them. 
The under fur of this species is rather soft and of a dark sooty brown, nearly black, much 
like the hair of the black hear. This is, however, mostly concealed by long bristles, six to 
eight inches long, the tips of which are of a greenish yellow. The concealed portion is dark 
brown, except the extreme base, which is whitish. The proportion of light and dark varies 
with the hair and the specimen. The central line of the belly is sooty brown, lighter than 
above. The limbs also are brownish, where not covered with spines, with their inner surfaces 
tinged with ashy. The spines are yellowish on the hack, whitish on the sides, tipped with 
brown. 
There are certain peculiarities in the skull of this species, as compared with that of E. 
dorsatus, which appear to he constant, at least as far as the specimens before me go. The chief 
of these is the great size of the nasal bones. These are of nearly uniforn width throughout, 
the sides nearly parallel, except that at about the posterior third they are wedged in between 
the frontals, the two forming an acute angle, projecting back as far as the eye-ball. This length 
of the hone is always two-fifths of the upper surface of the skull, sometimes even more. This 
character is well shown in Brandt’s figure. 
In E. dorsatus , the nasals begin to narrow almost from the anterior extremity, and do not 
extend as far between the frontals. Their length is rather less than one-third that of the upper 
line of the skull, or, at most, not exceeding one-third. 
In both species, the anterior molar of both jaws is considerably larger than the rest. 
