Ill 



cinifly resembles the foolli oi" Fig. 27, Plato YI, origiuiilly reteried lo /'. 

 delicatior, to pertain tt) tlu; same species, thougli it is slightly larger. 



The other specimen, apparently from the same individual, consists of a pair 

 of upper molars represented in Figs. 17, 1<S, Plate XXVII, magnified three 

 diameters. They have nearly the form and construction of those of the 

 Sciurides. 



The fore and aft diameter of the lower molar is 1.8 lines. The fore and 

 aft diameter of the upper molars is 1.8 lines, and the transverse diameter is 

 2 lines. 



Pakamys delicatissimus. 



A third and still smaller species of Paramys is indicated liy a specimen 

 consisting of the greater portion of the right ramus of a lower jaw contain- 

 ing all the molars, and a second specimen consisting of a small fragment of 

 another lower jaw containing the second molar. The first specimen of the 

 natural size is represented in Fig. 28, Plate VI. A view of the triturating 

 surfaces of the molars, magnified three diameters, is given in Fig. 29. The 

 molar series measures J an inch in length, and the animal was about the size 

 of the common gray squirrel. 



Comparative measurements are as follows : 



Leugtb of louver molar series 



Leiigtb of biatus iu advance of lower molar series 



Deptb of jaw below tbe second molar 



Fore and aft diameter of incisor 



Transverse diameter of incisor 



Fore and aft diameter of second molar 



Transverse diameter of second molar 



P. (lelica- 

 tus. 



Lines. 

 9 



C 



-1 

 5 



14 



p. delica- 

 tior. 



Lines. 



14 



P. delica- 

 tissimiLs. 



Lines. 

 G 



•1 



li 



H 

 n 



MYSOPS. 



Mysops minimus. 



A small rodent, intermediate in size to the common mouse and the brown 

 rat, is indicated by a specimen discovered by Dr. Carter at Grizzly Buttes 

 and sent to the author last summer. The S])ccim('n cousists of the median 

 portion of the right ramus of a lower jaw containing the last two molars, the 



