FOSSIL VERTEBRATES FROM SAN PEDRO VALLEY—GAZIN 503 
tion below M.. In specimens of 8S. ambigua of equivalent size and 
maturity the lower margin of the jaw usually exhibits an even con- 
vexity almost to the angle, or is but slightly irregular. The type 
mandible of S. pedroensis is further characterized by a short posterior 
portion as the distance between the carnassial tooth and the condyle 
is relatively long. 
The lower carnassial in the type is distinctly narrower across the 
protoconid-metaconid portion than in S. ambigua or other recent 
species of Spilogale having teeth of about the same size. The talonid 
portion, however, is not noticeably different in width although the 
basin appears somewhat more open lingually than in S. ambiqua, 
with no suggestion of a cuspule intermediate between the metaconid 
and entoconid. The canine tooth, on the other hand, is relatively 
robust and wider than in S. ambiqua, S. gracilis, or even S. arizonae. 
In P; the anterior style and posterior transverse crest, arising from 
the cingulum, are not so well developed as in the recent species of 
Arizona. 
The maxillary portion designated as the paratype, U.S.N.M. No. 
12869 (fig. 42), retains only the carnassial and molar. These teeth 
occlude very well with those in lower jaw No. 14683, presumed to 
be a female. They compare favorably in size with those in female 
skulls of Spilogale ambigua. In P* the anterior style is weak and 
the deuterocone shelf is not so expanded anteroposteriorly as in Recent 
species of comparable size. The width of the tooth across the deu- 
terocone is also less. The molar is markedly less expanded antero- 
posteriorly through the lingual portion than in any of the recent 
material examined, although the length of the buccal portion is nearly 
equal to that in specimens of S. ambigua. The transverse width of 
the molar is comparable to that in the living form. 
Comparison with other species of Spilogale described from the 
Pleistocene is limited to that with Spilogale marylandensis Gidley and 
Gazin** from Cumberland Cave. Spilogale pedroensis is readily 
distinguished from the Cumberland Cave form in exhibiting a much 
slenderer lower carnassial, particularly through the talonid portion. 
The longitudinal profile of the lower margin of the ramus, however, 
is similar in the two jaws, although the symphyseal portion is more 
abrupt in S. marylandensis. P, in S. marylandensis is more nearly 
oval in outline, as viewed from above, than in the Curtis ranch form. 
Spilogale pedroensis is distinct from species of Brachyprotoma in 
the less crowded premolars, smaller and narrower P,, and in the rela- 
tively more elongate talonid and better developed metastylid on M,. 
M' in Brachyprotoma pristina Brown, as represented in Cumberland 
Cave, shows a more expanded lingual portion than in S. pedroensis, 
*4 J. W. Gidley and C. L. Gazin, New Mammalia in the Pleistocene fauna from Cumberland 
Cave, Maryland. Journ. Mamm., vol. 14, pp. 343-857 (351-352), figs. 1-9 (4), 1933. 
