MURIDA2—SIGMODONTES—HESPEROMYS CALIFORNICUS. 99 
from average /eucopus in its sootiness, being, in fact, perhaps darker than deuco- 
pus ever becomes, unless in the “gossypinus” variety; and here the shade is 
different, being of a leaden grayish-brown, mixed with a good deal of black, 
yet watered throughout with fulvous. The color reaches to the wrist and 
ankle, but the upper surfaces of the hands and feet are whitish. On the 
sides, the color shades into a pale tawny-cinnamon or brownish-fulvous, very 
nearly of the same tint as in eremicus. The under parts can hardly be called 
white, owing to a suffusion of leaden-gray showing through the white tips of 
the hairs. The tail, as already stated, is dark, and not much paler below than 
above, with a very indistinct—sometimes inappreciable—dividing line. The 
ears show blackish in the dried state ; probably dusky flesh-color in life. The 
very long whiskers, many of which reach to the shoulder, are partly black 
and partly white. 
Among the Fort Tejon specimens (Xantus), we find two examples of 
californicus instantly distinguishable from the numbers of ‘gambeli” with 
which they are associated, and typically representing californicus. Several 
Tejon “gambeli”, indeed, show a tendency toward californicus in their large 
size and length of ears and tail, but nothing quite up to this remarkable form. 
Besides the dimensions tabulated below, No. 7478 shows these measurements : 
Nose to eye, 0.55; to ear, 1.02 ; ‘breadth of ear, 0.70; pencil of hairs at end 
of tail, 0.830; whiskers, 1.75. The soles, which have the ordinary six tuber- 
cles, are almost entirely naked; the ear is sparsely and delicately pilous. 
The hand and feet are white above; the tail is indistinctly bicolor, brown 
above, whitish below; it is nearly five inches long, with the terminal pencil 
about 5.25, which, the body being only 3.60, is the longest tail, both rela- 
tively and absolutely, we have seen in a United States Hesperomys. 
TABLE XXVII.— Measurements of four specimens of HESPEROMYS CALIFORNICUS. 
“3 Eig heals lies 
2 Date. Locality. Collector. g fe -) - & 3s 4 INES an 
I (fi S 2 ro z a B apecimen. 
Ale RI |e | a] a 
1.35 | 4.60 | 4.80 | 0.52] 1.05 | 0.75 | Dry. 
1156 | & | Nov. —, 1855 | Santa Clara, Cal.......-.. J.G. Cooper .--. f Spal We al aes ey oa ee Fresh. 
: hh Nyce Veo dg eet (al cee of ASOO) aaeeed en saen 1.00 | 0.70 | Dry. 
1157 | Q | Nov. —, 1855 |..----do--.--.-.--+---—---- v2 annee cece} Lee | 4.50 | 4.00 |......]...... 0.75 | Fresh. 
3670} ot |.---<. Binet Fort Tejon, Cal. ....--.-- eeNAntUsues se sce | eee | SA 00N | 4g00 Neon a 0.98 | 0.90 Dry. 
Thitte} |) op | beccessasse- 6a) acon: Geers ne oe nel | pete sO One aoa | 1.30 | 3.60 | 4.90!) 0.45 | 1.00 | 0.85 | Alcoholic. | 
The different H. californicus aside, all the California Hesperomys we have 
seen are referable to “gambeli”, excepting the Fort Crook series, which 
