Skulls of Aplodontia; all x 0.62. 



Fig. 7. A. cliryseola Kellogg: $, no. 13331, Mus. Vert. Zool., head of 

 Grizzly Creek, Trinity County, California. 



Fig. 8. A. californica (Peters): $, no. 18663, Mus. Vert. Zool., Blue 

 Cation, Placer County, California. 



Fig. 9. A. chryseola Kellogg: $, type, no. 13328, Mus. Vert. Zool., Jack- 

 son Lake, Siskiyou County, California. 



Note in A. chryseola (the two end skulls) : the short rostrum, 

 short and broad nasals, expanded frontal region, broad rostrum 

 posteriorly, less squarish zygomatic arch, broad interorbital con- 

 striction, and lengthened auditory tubes. 



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