20 



MONOGRAPUS OF NOHTH AMERICAN RODENTIA. 



notice is the length of tiiil. In N.Jloridana, tlie tail only exceptionally equals 

 the trunk vvitliout tiic head; in N. fuscipcs, tiie tail is only exceptionally so 

 short us this, ranging usually from a little more than length of the trunk to 

 tlie full length of tiic trunk aiui head together. Besides its length, the tail in 

 the dried specimens shows the peculiarity remarked hy Professor Baird, being 

 compressed for its terminal third, somewhat as in the muskrat. At first, we 

 thought this was a taxidermal or other accident, but all the specimens show 

 the same thing; so that, whether or not the tail be compressed in life, it, at 

 any rate, dries in that shape. Nothing of the sort occurs in N. Jhridana. 

 The pilosity of the tail is about the same in the two species. The ears 

 of fuscipcs are larger than those oi'Jloridana, although the general size of the 

 two animals is nearly the same. The soles o( fuscipes are nearly naked 

 throughout, but not perfectly so ; a scant hairiness occupying the posterior 

 third of the sole, which is densely furry in Jhridana. The general pelnge 

 of /«scy;cs is coarser and iiarsher than it is'm floridana, although the differ- 

 ence is not very noticeable ; not more so than that between prairie and forest 

 examples of N. cinerea. In other respects, of size, form, and pelage, we note 

 no essential characters. 



In color, however, there are likewise marked features, the most promi- 

 nent of which is the nearly uniform blackishness of the tail, and the next 

 most so is the duskiness of the hind feet. This peculiarity is uniform and 

 very conspicuous in all the specimens examined. The surface of the meta- 

 tarsus is dark-brown, like the outside of the leg; the toes being abruptly 

 white. This coloration and that of tiic tail are especially interesting in the 

 geographical connection mentioned below. In general color, the animal is 

 of a darker and warmer shade than ordinary jf?o/iV/aHa, and many times deeper 

 than the pale desert-breed of the latter from neighboring regions. The main 

 color is a strong reddisli-brown, overpowered with blackish on the back, but 

 very bright on the sides. The under parts are white, as usual ; the hairs oh 

 the middle line white to the very roots, but those along the sides of the belly 

 ashy at root. On the fore leg, the dark color runs to the wrist and then stops 

 abruptly ; on the hind, as stated, it reaches the roots of the toes. 



We have not specimens enough to show the full range of variation in 

 size and proportions; but tiiese, no doubt, are perfectly parallel with those 

 oijloiidana ; and, similarly, we cannot give the entire variation in color. We 

 Bhould judge, from the restricted area that this species occupies, that its colors 



