E. Lendell Cockrum

“ Since the measurements of specimens examined by us, as well as those recorded by Swarth (op. cit.) , fall within the range of those of the species Clethrionomys gapperi, and since the differences between phaeus and C. g. saturatus are of the kind and degree that separate subspecies in C. gapperi we employ the name combination Clethrionomys gapperi phaeus (Swarth) . C. g. saturatus, as understood by us, occurs to the southeast of C. g. phaeus in the Rocky Mountains of British Columbia, and in northeastern Washington, northern Idaho and northwestern Montana. ”

“ Bailey, in his revision of the American voles of the genus Microtus (N. Amer. Fauna, 17:20) , showed Arvicola modesta Baird to be a subspecies of Microtus pennsylvanicus but retained Microtus aztecus (Allen) as a distinct species. In describing M. aztecus he wrote "the size similar to M. pennsylvanicus, but with shorter tail and larger hindfoot; skull long; braincase narrow; interparietal long ..." and remarked that "Microtus aztecus belongs to the pennsylvanicus group. Externally it is not very different from modestus, but none of the specimens show any signs of intergradation ”

“ Differences between the gapperi group and the occidentalis group include: postpalatal bridge (complete in both groups) truncate posteriorly in the gapperi group and with a median, posteriorly directed, spine in the occidentalis group (this character is not evident in all specimens; some gapperi have a spine, and some occidentalis have the spine much reduced) ; dentition of the occidentalis group is heavier; enamel pattern of M3 and m1 in occidentalis more simplified—the number of salient and re-entrant angles tends to be reduced in adults of the occidentalis group. ”

“ There is considerable variation in color among the Washington-taken specimens of Microtus longicaudus. Animals from the eastern flanks of the Cascades average darker than those taken, north of the Snake River, still farther east in Washington. Possibly Dalquest (op. cit.) relied mainly upon this darker color in assigning the specimens from eastern Washington to M. l. halli. Relying principally upon cranial characters, we conclude that most of the specimens are better referred to M. l. mordax and that M. l. halli is restricted, in Washington, to the Blue Mountains. ”

“ Chicago Acad. Sci., 6:54, 1941) referred specimens from Rosiclaire, Illinois, to S. c. gossii. These specimens were not mentioned by Bole and Moulthrop (op. cit.) when they named S. c. saturatus although the specimens presumably would be referred to the newly-named subspecies. We have examined the pertinent specimens (Nos. 15781-15786 and 16049-16054 CNHM) and find that on the basis of dark color, long and slender skull, heavy incisors, and small cheek-teeth, they are referable to S. c. saturatus Bole and Moulthrop. None, however, has a tail so short as the type of S. c. saturatus. ”

“ In size and relative proportions it comes closest to E. dawsoni, from which it differs widely in coloration and more widely in cranial characters. With the long-tailed species south and east of its range there is no need of comparison."
Swarth (Univ. California Publ. Zool., 24:173, June 17, 1922) reported that three specimens from Flood Glacier and 23 from Great Glacier, British Columbia, and four from Sergief Island, at the mouth of the Stikine River, Alaska, were: "All E. wrangeli, indistinguishable from specimens at hand from Wrangell Island." ”

“ They differ from P. p. nemoralis of comparable age in shorter tooth-row and generally smaller skull. The interorbital region, however, is wider. In all of the features mentioned above, the specimens in question agree with Pitymys pinetorum scalopsoides, to which subspecies they are here referred.
Microtus pennsylvanicus aztecus (Allen)
1893. Arvicola (Mynomes) aztecus Allen, Bull. Amer. Mus. Nat. Hist., 5:73, April 28, type from Aztec, 5900 ft., San Juan County, New Mexico. ”

“ E Manassa, Conejos County, Colorado, and with four adults from Saguache County, Colorado (all in KU) , reveals that the supposed "well marked" external and cranial differences between the two forms are not nearly so evident as was indicated by Bailey. ”

“ Fauna, 50:30-31, August 5, 1927) had only eight specimens of this subspecies available when he revised the genus Synaptomys. Of these eight (Maine: Mount Katahdin, 2; New Brunswick: Near Bathurst, 1; New Hampshire: Fabyans, 1, the type; Quebec: St. Rose, 4) , only the type and one of the specimens from St. Rose are adults. Concerning the others, Howell wrote (op. cit.:31) : "The example from near Bathurst is not adult and has a damaged skull, so is identified provisionally. All other specimens are too young for positive diagnosis." ”