NO. I LOWER EOCENE MAMMALIAN FAUNAS — GAZIN IQ 



tion of relationships (see Gazin, 1959, p. 135). All of these are 

 discussed in the systematic portion of this paper, as listed in the 

 preceding section. Of these, all but Peratherhim, Trogosusf, Ab- 

 sarokius, Micro paramys, and the brontotheriid near P. fontinalis 

 are represented in the New Fork fauna. Only Trogosusf and the 

 brontotheriid appear significant in this difference. 



I have earlier (1959) discussed the possibility of the Cathedral 

 Bluffs including upwards beds somewhat later than are represented 

 in the New Fork, particularly to the north of the Washakie Basin 

 in the region of the Oregon Buttes and Cyclone Rim. Although this 

 in no way disturbs the probable contemporaneity of the two sets 

 of beds, at least so far as their relation with the Tipton tongue is 

 concerned, it may be noted that New Fork sequence as exposed in 

 the type area is scarcely more than a remnant near its basinward 

 periphery, where it interfingers with the Wilkins Peak. Most of its 

 faunal remains were recovered in the lower part, no great distance 

 above the Tipton (Fontenelle) tongue, except for Bathyopsis, which 

 was discovered several miles farther south on Alkali Creek and 

 possibly a little higher in the section. 



Investigation, furthermore, of the particular field occurrences of 

 Trogosusf, sp., and the brontotheriid, near Palaeosyopsf fontinalis 

 (earlier listed as Eotitanops, sp.), discloses that both were found in 

 sec. 4, T. 15 N., R. 93 W. This is evidently locality i on Morris's 

 map (1954, p. 198) and clearly high in the section, as it is near the 

 contact with the overlying Laney shale. Both also have been found 

 in beds mapped as belonging to the Cathedral Bluffs tongue in the 

 Continental Divide Basin farther to the north. The Trogosiis occur- 

 rence reported by Nace (1939, pp. 17, 26-27) was described as 

 occurring 75 feet below the top of the Cathedral Bluffs tongue in 

 the northwest part of T. 26 N., R. 98 W. The brontotheriid near 

 Palaeosyopsf fontinalis was found by me very near the top of the 

 red beds in the Oregon Buttes area, immediately to the southwest of 

 the Continental Peak at the north margin of Sweetwater County. 

 The significance of the brontotheriid occurrences is discussed in the 

 systematic section of this paper. The implication that a "Bridger A" 

 level is represented is probably meaningless. The Palaeosyopsf 

 fontinalis type may well have been found in a sandy lens of the 

 Wilkins Peak member. Robinson (MS.) has shown that the Huer- 

 fano B fauna, which includes Palaeosyopsf fontinalis, is associated 

 with a Lost Cabin fauna rather than one truly Bridgerian. 



It is now evident that Trogosus was not actually in association with 



