1912] Kellogg: Pleistocene Rodents of California 



159 



Creek Cave by W. J. Sinclair, 6 the type being the "anterior two- 

 thirds of a skull of an adult individual, in which the teeth are 

 not much reduced by wear," and the main points of differentia- 

 tion being that in the fossil form "the rostrum and incisive 

 foramina are decidedly shorter . . . than in T. cinerea . . . the 

 premaxillae extend farther back beyond the nasals, the nasals 

 taper more posteriorly, and the frontals have a greater inter- 

 orbital width." Also in the lower mandibles of T. spelaea "the 

 enamel loops of the molars [are] more evenly balanced on the 

 two sides of the axis of the tooth row." According to E. A. 

 Goldman 7 in his revision of the genus Neotoma, typical N. cinerea 

 is not considered to range into northern California, but instead 

 that region is occupied by N. c. occielentalis. The following com- 

 parisons are made with specimens of that subspecies. 



The type of Teonoma spelaea, no. 536'2, is the only specimen 

 available from which all the measurements in support of the 

 various specific characters can be obtained ; moreover the skull 

 is that of a young adult individual which may not have attained 

 full size. There are two other portions of skulls from Potter 

 Creek Cave, nos. 3550 and 6341, but they are broken so that 

 measurements of all the points cannot be taken. In Samwel 

 Cave all the specimens found were lower mandibles, so no cor- 

 roborative measurements can be obtained from that source. 

 Taking, therefore, the measurements of the type only as given in 

 the description already cited, and comparing them with those 

 of three specimens of young adult females of N. c. occielentalis, 

 from the collection of the California Museum of Vertebrate 

 Zoology, it is found that in the type of the fossil form the 

 incisive foramina are longer, and the rostrum, that is the dis- 

 tance from the base of P 4 to the anterior face of the incisor, is 

 longer. The extension of the premaxillae is less than that of one 

 of the specimens with which it is compared, and greater than 

 that of the other two, showing that this is a variable character. 

 The frontal width is less than a millimeter greater. The main 

 points in which the fossil form differed from N. c. occielentalis 

 were in a longer upper tooth row and larger teeth, points which, 



Univ. Calif. Publ. Bull. Dept. Geol., vol. 4, no. 7, p. 147, 1905. 

 t N. Amer. Fauna, no. 31. 



