300 



University of California Publications in Zoology [Vol.12 



Aplodontia pacifica Merriam, described from Newport, mouth of 

 Yaquina Bay, Oregon, is the darkest species of mountain beaver known 

 heretofore, and is the smallest species as yet characterized. 



Transmitted January 22, 1914. 



Table of Cranial Measurements op Aplodontia phaea and A. nigra 

 All measurements in millimeters 



3 = IS I | a 3'S tS.5 3s M PSaS 



Aplodontia phaea 



20309 jj 6 mi. W. Inverness, 



Marin Co., Calif... 23.6 9.S 41.5 7.3 4.2 15.8 59.0 26.8 

 8974 J Lagunitas, Marin 



Co., Calif 9.9 6.2 4.6 15.3 55.4 27.6 



20311 ? 6 mi. W. Inverness, 



Marin Co., Calif... 22.1 9.8 44.3 6.5 4.4 16.0 56.9 2S.1 

 20305 $ 6 mi. W. Inverness, 



Marin Co., Calif... 21.8 9.8 45.0 6.5 4.1 17.3 58.5 29.6 



Aplodontia nigra 



20320 <$ Point Arena, Men 



doeino Co., Calif.. 



20321 J Point Arena, Men 



doeino Co., Calif.. 

 20319 <$ Point Arena. Men 



doeino Co., Calif.. 

 2031S jj Point Arena, Men 



doeino Co., < 'a lit. 



23.5 11.0 46.8 6.8 5.6 17.5 56.9 30.8 



21.9 10.0 45.6 5.5 4.8 15.4 52.9 29.1 



22.2 10.9 49.1 5.0 4.9 15.3 55.0 27.8 



22.7 10.5 46.2 5.2 5.7 14.5 52.9 27.4 



1 Most anterior point on nasal bones to most posterior point. 



2 Greatest width of nasals, across both of them. 



s With cranium resting on its dorsal surface, rostrum pointing away from 

 the worker, the greatest length of the foramen on the right side. 



* Taken at expansion of interpterygoid fossa immediately back of hard palate. 



5 Most lateral point on foramen ovale to the point farthest laterally (with 

 reference to the skull) on zygomatic side of auditory tube. 



