APLODONTID.E 93 



Type locality, Sherwoods, Mendocino County, California. 



I cang-ht the type of this subspecies in a thick redwood 

 forest, in a steel trap baited with meat and set for mink at the 

 roots of a large redwood tree a few inches from a brook. 



Family. Aplodontidae. Sfaveli^kls. 



Skull massive, flat, much constricted interorbitally, excess- 

 ively widened posteriorly; brain case comparatively small; zygo- 

 matic arches widened posteriorly; no postorbital processes; 

 anteorbital foramen small, low, oval ; nasals short and broad ; 

 audital bullae peculiar, tubular, being greatly lengthened later- 

 ally; descending ramus of lower jaw very wide with a project- 

 ing lateral angular flange; coronoid process high; molariform 

 teeth simple, rortless, prismatic, penultimate upper premolar 

 present but small ; five toes on each foot, the inner toe of front 

 foot small but functional ; tibia and fibula separate though closely 

 apposed; outlets of genito-urinal and digestive organs separate. 



This peculiar family contains but a single genus, consisting 

 of half a dozen species and subspecies. It appears to^ be one of 

 the most primitive types of mammals now existing, having no 

 very close afiinities with any other living family. It is of lim- 

 ited distribution, being found only in western North America 

 from California to British Columbia, in the Sierra Nevada and 

 Cascade Mountains and in parts of the lower region west to 

 the Pacific coast. 



The food is twigs, stems and leaves of shrubs and plants, 

 mostly perennial. They are plantigrade, nocturnal, semi-aquatic, 

 fossorial, living in burrows in wet ground. The sexes are alike; 

 the young are darker in color but are otherwise similar to the 

 adults. There are five pairs of mammse, nearly equally distrib- 

 uted from the armpit to the groin. 



Genus Aplodontia Richardson. (Simple-tooth.) 

 Eyes small; ears projecting a short distance above the sur- 



