382 HETEROMYS. OCTODONTIDJE. LONCHERIN^B. 



NELSON'S SPINY MOUSE. 



Type locality. Pinabete, State of Chiapas, Mexico. 



Genl. Char. Size very large; ears large. Skull long, slender 

 superorbital beads faint. 



Color. Above mouse gray, darkest on top of head; upper lip, 

 hands, feet, under parts, inner side of fore legs and streak on hind 

 leg white; hind feet clouded above; ears without white edges. 



Measurements. Total length, 356; tail vertebrae, 195; hind 

 foot, 43.5. 



Fam. VI. Octodontidse. The Octodonts. 



This Family has been divided into several subfamilies, only two 

 of which, the CAPROMYIN^; and LONCHERIN^;, are necessary to be 

 mentioned as coming within the scope of this work. Save one 

 species, the Coypu (Myocastor coypu), yielding the "Nutria fur" of 

 commerce, the members of this family are not generally known 

 except to naturalists, and among them, in the New World and on 

 certain of its islands, are found the curious Tree Rats of the genus 

 CAPROMYS, from which the name of the first of the above-mentioned 

 subfamilies is derived; the allied PLAGIODONTIA and various species 

 of Spiny Rats of different genera compose the other subfamily 

 LONCHERIN.E. Their trivial names are Hedge-hog or Spiny Rats, 

 as many have variously shaped spines mingled with the fur. Some 

 are of considerable size, and all have a more or less harsh fur, in some 

 instances even bristly. The various species are arboreal, terrestial, 

 or aquatic in habits, the Coypu having webbed hind feet and a cylin- 

 drical, tapering otter-like tail. The technical characters by which 

 these subfamilies are separated exist chiefly in the skull and teeth. 



Sub f am. I. Lioncherinee. 



In the succeeding genera the fur is usually mixed with flattened 

 lancet-shaped spines, contracted at the base, and acutely pointed. 

 Sometimes they are ridged, and never project beyond the hair. 

 Some species are prettily marked in brown and white, but many 

 have sombre hues only. Certain members of this subfamily are 

 destitute of spines, and so the trivial names for these animals would 

 be inappropriate for them, but it will answer well enough for the 

 majority of the species found within the limits of this work. 



