46 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I44 



Specimens from the Washakie Basin that I have tentatively re- 

 ferred to this species include a left mandibular ramus with M1-M3, 

 U.S.N.M. No. 22419, and an isolated lower molar in the University 

 of California collection from the Knight escarpment beneath the 

 Tipton tongue between Dad and Baggs, Wyo. There is, moreover, 

 a specimen, U.S.N.M. No. 22420, that includes a jaw portion and 

 three associated lower teeth from the Cathedral Bluffs on the west 

 side of the basin, that may be this species. 



PARAMYS MAJOR Loomis 



A maxilla with P* and M^ (U.S.N.M. No. 22414) collected at 

 the Muddy Creek locality north of Big Piney in 1954, has teeth of a 

 size that indicate that a third specimen now represents large Paramys 

 major in the La Barge fauna. Two lower jaws in the Princeton 

 collection (Nos. 16106 and 16 127), from beneath the Tipton tongue 

 south of Dad, are also surely of this species. 



I have not found this species in Knight beds older than Lost 

 Cabin, but the New Fork beds above the Fontenelle tongue have 

 produced at least five specimens that would appear to be referable to 

 it. From the Cathedral Bluffs of the Washakie Basin a single iso- 

 lated upper tooth in the Princeton collection corresponds well in size. 



REITHROPARAMYS, sp. 



A single lower jaw with only M2 preserved, U.S.N.M. No. 22380, 

 from the saddle north of Fossil Butte in the Fossil Basin, is regarded 

 by Wood as representing a species of Reithro paramys, near a form 

 that he is describing as new in his forthcoming study of the family. 



MICROPARAMYS, sp. 



A lower jaw in the Princeton collection from the Cathedral Bluffs 

 beds, U.P. No. 161 12, is recognized by Wood as representing this 

 genus. Description of the species represented is to appear in his 

 report. 



SCIURAVIDAE 



KNIGHTOMYS SENIOR (Gazin) 



(Plate 5, figures 5 and 6) 



The genus Knightornys was proposed (Gazin, 1961) for the 

 La Barge species that had originally been described as Tillomys senior 

 in 1952. The generic characters may again be summarized as follows : 

 Lower cheek teeth anteroposteriorly short, broad across talonid and 



