Sabinas, 1050 ft., 2.

+Cratogeomys castanops ustulatus+ new subspecies

_Type._--Female, adult, skin and skull, No. 34589, Univ. Kansas Mus.
Nat. Hist., Don Martin, 800 ft., Coahuila; 19 August 1949; obtained by
W. Kim Clark, original number 1034.

_Distribution._--Extreme northeastern Coahuila from the vicinity of
Presa Don Martin southward into northwestern Neuvo Leon in the valley
of the Rio Salado and its tributaries at least as far south as the
vicinity of Vallecillo (see fig. 1).

_Diagnosis._--Body large for species (see tables 1 and 2); hind foot
short; upper parts Apricot Buff (in fresh summer pelage) and
Salmon-Buff strongly mixed with black (in fresh winter pelage);
underparts Light Ochraceous-Buff; skull large, especially in females,
and broad; zygomatic arches widely flaring; palate long; rostrum
broad; nasals long; mastoid and tympanic bullae not conspicuously
inflated; incisors narrow; maxillary teeth large.

_Comparisons._--From _Cratogeomys castanops bullatus_ found to the
north, _ustulatus_ differs in: Body larger; tail shorter; upper parts
darker, more rufous and less buffy; skull larger, especially in
palate, nasals, and rostrum; zygomata more widely flaring; tympanic
bullae less inflated; incisors slightly larger; maxillary teeth
larger. From topotypes of _Cratogeomys castanops tamaulipensis_
found to the southeast, _ustulatus_ differs in: Body larger; upper
parts, in winter pelage, darker, more rufous and less buffy;
underparts paler; skull larger, especially in palate, rostrum and
nasals; zygomata more widely flaring; tympanic bullae more inflated;
pterygoids larger; basioccipital narrower, its sides parallel instead
of convex; maxillary teeth smaller. From _Cratogeomys castanops
subsimus_, found to the southwest, _ustulatus_ differs in: Tail
shorter; hind foot smaller; upper parts darker, more rufous and less
pinkish-buff; skull shorter; zygomata less widely flaring; palate
shorter; rostrum averaging slightly narrower; nasals shorter; incisors
narrower; maxillary teeth slightly smaller. For comparison of
_ustulatus_ with the subspecies of _C. castanops_ to the southwest,
see account of that subspecies to follow.

_Remarks._--_Cratogeomys castanops ustulatus_ is a large-sized pocket
gopher with a relatively larger, skull. In size oL skull, _ustulatus_
is exceeded only by _C. c. subsimus_ found beyond the mountains in the
southern part of Coahuila. In size, _ustulatus_ differs so mar