potypes of _Microtus aztecus_ with a series of nine
adults of _M. p. modestus_ from 1 mi. S, 2 mi. E Eagle Nest, 8100 ft.,
Colfax County, New Mexico, with three adults from 1-1/2 mi. 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.

The cranial differences that exist between these two forms (narrower
nasals, slightly longer interparietal, slightly longer and narrower
skull in _aztecus_) are evident only as averages. Although
geographically intermediate specimens are lacking, the morphological
differences between the two kinds of animals are of the degree and kind
that separate subspecies, rather than species. We therefore judge _M.
aztecus_ (Allen) to be only subspecifically distinct from _M.
pennsylvanicus modestus_ and employ the name _Microtus pennsylvanicus
aztecus_.

Microtus pennsylvanicus funebris (Dale)

1940. _Microtus pennsylvanicus funebris_ Dale, Jour. Mamm., 21:338,
August 14, type from Coldstream, 1450 ft., 3-1/2 mi. SE Vernon,
British Columbia.

Taylor and Shaw (Occas. Papers Charles R. Conner Mus., State College
Washington, 2:24, December, 1929) list under _Microtus nanus_ [=
_montanus_] _canescens_ material from Calispell Peak, Washington.
Probably the basis for this record is a specimen in the Biological
Surveys collection (adult male, 236474) taken on May 9, 1921, by G. G.
Cantwell, and labelled as Calispell Peak, 9 mi. W Locke, 3500 ft., Pend
Oreille County. An examination (by Hall and Kelson) of the specimen
discloses that it is of the species _Microtus pennsylvanicus_, and that
it falls within the geographic range ascribed to the subspecies
_Microtus pennsylvanicus funebris_ by Dalquest (Univ. Kansas Publ.,
Mus. Nat. Hist., 2:346, April 9, 1948).

Microtus oeconomus amakensis (Murie)

1930. _Microtus amakensis_ Murie, Jour. Mamm., 11:74, February 11,
type from Amak Island, Bering Sea, Alaska.

When Murie (Jour. Mamm., 11:75, February 11, 1930) named the meadow
mouse from Amak Island, Alaska, as _amakensis_, he arranged it as a
separate species. One of us (Hall) and K. R. Kelson examined the type
and topotypes of _amakensis_ in the Biological Surveys collection in
the U. S. National Museum and compared them with series of _Microtus
oeconomus operarius_, _M. o.