E. hatcheri Hay 1915
The highly reconstructed type skull and associated mandible USNM 7868 come from Hay Springs. The muzzle seems long (Fig.1). The protocones are short and not grooved (Fig.2).
The lower cheek teeth are typically caballine; ectoflexids are shallow even on the molars (...)
E. alaskae Hay 1913b, type: USNM 7700, from Sullivan’s Creek, Tofty, Central Alaska. Dscribed as E. niobrarensis alaskae.
The type belongs to an adult male (Fig.1).
The muzzle is longer than in E. lambei and E. niobrarensis.
Similar skulls (Fig.2) are FAM 6001, 60010, 60011, 60071 (Fig.3, (...)
E. niobrarensis Hay 1913a, type: USNM 4999, Hay Springs, Nebraska, 300ky?
The type cranium belongs to a young adult mare (Fig.1) and 1bis. I have seen only a cast. On it, the cranial height is unusually large and the basilar proportions cannot be ascertained.
As it is, the information on the (...)
E. lambei Hay 1917, type: USNM 8426 Gold Run Creek (=Dawson 32), Yukon, ca 15000 years old. The skull L 1-1222 probably comes from the same localitry (Harington and Clulow, 1973).
Probably best adapted to cold as shown by short muzzles and to hard food as shown by big teeth and long protocones. (...)
There are three caballine crania from the Irvingtonian (300 BP?) of Hay Springs, Nebraska.
E. niobrarensis, Hay 1913, type skull UNSM 4999
I have studied only a cast of the type; Azzaroli mentioned the original appeared to have been heavily reconstructed.
E. hatcheri, Hay 1915, type skull (...)
I consider as certain ‘Caballines’ fossils in which cranium, and upper cheek teeth, and lower cheek teeth have caballine characters.
1. According to Azzarroli (1998) the first caballine in North America may be represented by the right mandible UNSM 93078, a fragmental jaw UNSM 93082, and two MT (...)