256 University of California Publications in Zoology. (Vou.5 
Peromyscus macrorhinus Rhoads. Rhoads White-footed Mouse. 
Stephens secured eight specimens at Helm Bay and one at 
Etolin Island during September. These agree well with the 
topotype series in size but are slightly lighter in color than the 
August material in the Biological Survey collection. 
Microtus admiraltiae, new species. Admiralty Vole. 
Type from Windfall Harbor, Admiralty Island, Alaska; 
adult female, No. 118, Uniy. Cal. Mus. Vert. Zool.; collected by 
Joseph Dixon, May 4, 1907; orig. No. 25. 
CHARACTERS.—Upper incisors long and straight, their are 
forming a wide angle; coloration of upperparts grizzled brown- 
ish. 
CoLoraTion.—Upperparts grizzled grayish brown, the brown 
predominating; sides somewhat paler and grayer but changing 
rather abruptly to the light grayish wash of the underparts. 
Feet grayish. Tail well haired, sharply bicolor, dusky brown 
above, whitish below. 
SkuutL—Skull remarkably wide with wide-spreading zygo- 
matic arches; interorbital region without any prominent angles, 
rounded; upper incisors long and straight, very little decurved, 
their are forming a wide angle; brain case large, flattened 
above. 
MEASUREMENTS.—T ype: total length, 158; tail vertebrae, 
48; hind foot, 21. Average of five adults: total length, 156; 
tail vertebrae, 45; hind foot, 21. Skull (type): Hensel, 24.2; 
zygomatic breadth, 15.2; mastoid width, 11.7; length of dias- 
tema, 10.4. Average of five adults: Hensel, 23.9; zygomatic 
breadth, 15.1; mastoid width, 11.8; length of diastema, 10.3. 
The straight, projecting incisors at onee distinguish this 
form from drummondi and its allies of the adjacent mainland. 
The diastema measured from the anterior border of the alveolus 
of the first upper molar to the outside border of the upper in- 
cisor averages a millimeter greater in this form than in drum- 
mondi. The Admiralty series, compared with skulls of drum- 
mondi from Bennett, Alaska, the only loeality from which this 
form is known in the immediate region, shows the skull to be 
