MURIDAI—SIGMODONTES—H. LEUCOPUS SONORIENSIS. 87 
others, the tail seems to run a /itt/e shorter than an average, but not tangibly 
so, nor is it beyond extremes we have demonstrated for ordinary deucopus. 
The following series is from the wooded mountainous region of 
Arizona :— 
TABLE XXII.—Measurements of fourteen specimens of HESPEROMYS, apparently SONORIENSIS, from Northern 
Arizona. 
i =| 0s Ss =) 
2 , Date. Locality. Collector. z 3 | = = cs ‘ Remarks. 
ii ike o-| 34 5 = & 
A ia) 23) a & is) 8 
78443 | op | May 3, 1865 E. Cones.......-...| 3.60 | 3.50 | 0.37 | 0.76 0.76 | Dry; adult. 
2450 | 9 | Mar. 29, 1865 atl O amen -| 3.75 | 2.25 | 0.32 | 0.75 | 0.45 |.-.-do. 
8441 | fo | Feb. 2, 1865 OO) <'aen 3.90 | 2.75 | --.-.| 0.75 | 0.65 |.-..do. 
eae Q July 12, 1864 do ..........-..] 3.40 | 2.60 | 0.33 | 0.73 | 0.64 |..-.do. 
8442 | ot | May 11, 1865 dosase- ees 3.60 [ 2.25 | 0.32 | 0.72 | 0.62 |....do. 
6449 | O | Jan. 28, 1865 AG Score lac a 3.50 | 2.30 | 0.35 | 0.74 | 0.71 .-do. 
8440 | 2 | May 11, 1865 (leo sesece 3.10 | 2.50 |...... 0.78 | 0.69 |....do. 
8445 | o | Feb. 15, 1865 (itKescHeeeerae 3.30 | 2.30 |...... US7 by |e sc Sees tay 
8446 | ¢ | Jan. 31,1865 SOO tee mctvoacces Mito | 22d Jere | 0.79 |o-. Dry; youngish. 
2448 | ¢ | Jan. 31,1865 done ote se 3h10)))02590) |e 0:78 |2---=- .-.-do 
8454 |... | Jan, 23, 1865 2. 80 (7 (3),| ene ae Dry; young. 
#444 |... Apr. 10, 1865 0.75 |:...- eo d0; 
8451 | -..| Janu. 1, 1865 OSH |oneaee| [ase a do 
8471 oS May 24, 1865 O374)|s-53: s2=2d0; 
aD Oe eee Maro Lobo a= OMe eee mas, dete ce asl OO iad ce seco s 50 | Dene] peeenee eens [ecees “ea = Dry; very young. 
SEES? |p Seed | NOs tel BER AG oa eeeSoORe ened) sen UL Cr aEScoReerad| adcceo| esters! sascri\eeeemc| ence Dry; suckling 
of 8450. 
SbaeEe ome) Mavis 20H LEGS) |e oa LO) oem ania ew aslo ee aa CO Racccmoarenpod recone) ecssca\ bacac-| enema) mesood| Petty 
This series* was taken in the store-houses at Fort Whipple, where the 
mice had taken up. their quarters, and seemed as thoroughly domesticated as 
ordinary house-mice. It unquestionably represents but a single species, read- 
ily referable to the variety sonoriensis, which we here have in all stages, from 
the suckling young to the adult. With the single exception below mentioned, 
there is nothing whatever of the evemicus stamp in the series. The soles are 
very furry indeed, owing, probably, to the fact that the animals were mostly 
taken in cold weather; the tails are well haired and bicolor, and noticeably short. 
In general coloration, these animals are darker than Palmer’s desert examples, 
and, in fact, not distinguishable in this respect from ordinary /ewcopus of New 
England. But the ears seem to run a little larger than in Eastern United States 
examples; and they reach, in No. 8443, a size equal to that of eremicus. This 
same No. 8443 also differs from all the rest in having the tail barely shorter 
than the head and body, instead of upward of an inch shorter, and indistinctly 
bicolor. Its coloration leans toward that of eveméaus in the pinkish-fulvous 
*TIt represents what we erroneously called “ Hesperomys eremicus” in our article in the American 
Naturalist, i, 398; but the name is probably correct as far as 8443 is concerned. 
