1893.] Zoology. 55 
and I therefore propose for the New Jersey animal the name Evotomys 
gapperi rhoadsii in honor of my friend, Mr. Samuel N. Rhoads. 
The comparison of a series of skulls of E. gapperti and E. g. rhoadsii 
fails to show any constant differential characters, though the immature 
specimens of the new race are peculiar in the structure of the last 
upper molars. In these teeth the first reentrant angle on the inside is 
opposite the second salient angle on the outside instead of the first 
reentrant angle as is the casein the adults of both forms. One young 
specimen of E. gapperii shows a tendency to this structure, but in all 
the other specimens that I have examined the reentrant angles meet, 
and the outer one is deflected posteriorly. 
In proportions the New Jersey race seems to average rather smaller 
than E. gupperii from the Adirondacks, while the tail is shorter and 
the feet slightly longer than in that species. 
As regards coloration E. g. rhoadsii is everywhere darker than E. 
gapperii, and has a plumbeous cast on the sides and flanks, while it 
lacks almost entirely the buff suffusion generally seen on the sides and 
under surface of the latter species. 
Above the color is decidedly darker than in E. gapperii, and there 
are a great many more black hairs scattered over the back. The red- 
dish area is not so well defined and the color is darker—more of a 
mahogany shade. The tail is distinctly bicolor, but the upper surface 
is darker than in E. gapperii, and the feet have a decidedly gray suf- 
fusion, contrasting strongly with the pure white of the latter species. 
Some immature specimens of E. gapperii approach adult E. g. rhoadsii 
in general coloration, but the young of the latter race with which 
they should properly be compared have scarcely a trace of the reddish 
dorsal area, the middle of the back r Being brownish and the sides gray. 
The table on next page, will show the ts of the 
two forms, the specimens of E. gapperii being selected from a series 
kindly loaned me by Mr. G. S. Miller. 
Dr. C. Hart Merriam, of the Department of Agriculture, Washing- 
ton, D. C., has kindly examined my New Jersey material and compared 
it with Evotomys carolinensis and other species to which I had not 
access, but its closest relationship appears to be with E. gapperti. All 
the specimens of this new mouse so far secured were taken in a cran- 
berry bog on the Egg Harbor River, about a mile above the town of 
May’s Landing, N. J. The unexpected occurrence of this boreal genus 
well within the Carolinian Fauna may probably be accounted for by the 
theory already advanced by Dr. Merriam that in these damp bogs, 
where the temperature is much lower than in the surrounding dry 
