174 MEMOIRS OF THE CARNEGIE MUSEUM 
type of S. pansus may also have been derived, along with ‘ Hwmys’ loxodon, from 
similar’ formation underlying the normal ‘ Loup Fork’ (Upper Miocene) of New 
Mexico.” 
Regarding this genus “ Humys” loxodon, Cope says® that Dr. Hayden regards 
the Santa Fé Marls as late Tertiary, ‘but without special determination or coérdi- 
nation with other known lacustrine formations of this continent.” 
The fauna from this formation is, according to Cope, characteristically Loup 
Fork with the following list of genera: Hippotherium, Protohippus, Procamelus, 
Cosoryx, Merychyus, and known Pliocene species of other genera, among which may 
be mentioned Canis, Aceratheriwm, ete.” 
In the paper referred to,? Cope described a number of new species from the 
Santa Fé Marls, among which is (p. 150) Hesperomys loxodon. This ‘‘ was found in 
the same deposits as the preceding species”? which is Cosoryx teres, described on the 
same page (150). 
In his later’ publication, after having discussed Stenofiber pansus, Cope provision- 
ally refers Hesperomys loxodon to ‘‘ Humys” loxodon, and quotes the original de- 
scription in full, without regarding the fact that Stencofiber pansus and not Cosoryx 
teres is here the preceding species.* 
In Steneofiber pansus, according to Cope, p* of both series is conspicuously larger 
than the rest of the cheek teeth. The second and third molars are similar in pro- 
portions in S. pansus. From Cope’s illustration it appears, that p* retains the in- 
ternal and external enamel inflections for a considerable length of time after the 
maturity of the animal. “he inferior incisors are almost quadrate in section, the 
two posterior angles being rounded. ‘The enamel does not extend on either side, 
and is smooth ; its transverse section is slightly convex. . . . The auditory bulle 
are very large; they are subsemiglobular and compressed. ‘The humerus preserved 
lacks epiphyses ; its sections are triangular, owing to the presence of aliform angles. 
One proximal [angle] directed inward and backward is much more prominent than 
the deltoid crest opposite to it.” The deltoid crest, then, is perhaps moderately 
prominent. The olecranon process of the ulna is short. 
In Bull. Americ. Mus., Vol. XX., 1904, pp. 257-260, Dr. Matthew and Mr. 
Gidley describe a skull as Steneofiber pansus which was found in the lower Miocene 
1° Rosebud Beds,’’ which, according to Matthew and Gidley, underly the true Loup Fork, and overly the White 
River on the Rosebud Reservation in South Dakota. 
2 Proc. Philad. Acad., 1874, p. 147. 
3U. 8S. Gogr. Surv., W. 100 Mer., IV., p. 300. 1877. 
‘This genus Humys is perhaps not the true Oligocene genus, as it was found apparently in a much later horizon. 
Cope’s description of the specimen is rather brief, and the figures given are unsatisfactory, so that without a study of 
the type nothing definite can be said regarding its relation to the genus from the Oreodon beds. 
