FOSSIL VERTEBRATES FROM SAN PEDRO VALLEY—GAZIN 499 
The carapace of Glyptotheriwm arizonae resembles rather notice- 
ably that of Glyptotherium texanum® from the Blanco beds, in the 
pattern and arrangement of the scutes in different areas. Also, the 
tail armature is composed of 8 free rings and the terminal cone as 
in @. tecanum. The number of caudal vertebrae is not less than 12, 
and at least 10 had chevrons. G. arizonae differs from G. texanum 
essentially in the greater development of the marginal scutes of the 
carapace, and the imbricated anterolateral portions appear to be 
more noticeably flexed from the main body of the carapace; how- 
ever, the figured carapace of G. arizonae was partially crushed as 
found. The posterior segments of the movable rings of the tail 
armature also exhibit better developed bosses, and the eighth ring is 
completely biserial, also, the two anterior of the three ringlike seg- 
ments of the terminal cone are more nearly biserial through inter- 
calated scutes than in G. tewanum. 
G. arizonae is more advanced and certainly specifically distinct 
from G@. texanum; however, the differences may not be sufficiently im- 
portant to warrant generic separation. Boreostracon floridanus * or 
rivipacis ** is from a much later stage of the Pleistocene and the scutes 
figured by Holmes and Simpson apparently exhibit a different type of 
surface pattern, particularly in the middorsal areas where the marginal] 
figures of the scutes are more noticeably grooved and less sharply de- 
fined than in G. arizonae, and these marginal figures do not appear 
to interfinger with those of adjacent scutes to the extent seen in G. 
arizonae, 
In Brachyostracon mexicanus (Cuataparo and Ramirez)” the in- 
terfingering type of scutes, in which the marginal figures of each are 
well defined, apparently extend to the periphery of the carapace, al- 
though in the illustrations of Brachyostracon cylindricus Brown the 
more lateral scutes appear serially aranged with better developed 
bosslike central areas than in B. mewxicanus. 
Order CARNIVORA 
CANIS EDWARDII, new species 
FIGURE 41 
Holotype.—Skull and mandible, U.S.N.M. No. 12862. 
Locality —Abount 2 miles northeast by ‘east of Curtis ranch house, 
San Pedro Valley, Ariz. 
Horizon.—Curtis ranch, early Pleistocene. 
12H. F. Osborn, Bull. Amer. Mus. Nat. Hist., vol. 19, pp. 491-494, 1903. 
*G. G. Simpson, Bull. Amer. Mus. Nat. Hist., vol. 56, pp. 581-583, 1929; and W. W. 
Holmes and G. G. Simpson, ibid, vol. 59, pp. 405-418, 1931. 
210, P. Hay, Carnegie Inst. Washington Publ. 322, pp. 39-40, 381, 1923. 
*2See Barnum Brown, Bull. Amer. Mus. Nat. Hist., vol. 31, pp. 167-177, 1912. 
