62 



NORTH AMERICAN FAUNA. 



[No. 38. 



horizontal ramus of mandible narrow and weak; teetli, especially jSrst 

 incisors, small. 



Measurements, — ^Average of 3 adult males from Eureka, Humboldt 

 County, Cal. : Total length, 167 (163-175) ; tail vertebrge, 33.7 (31-35) ; 

 hind foot, 20.7 (20-22). SlcuU: Average of 2 skulls of adult males 

 from Ferndale, Humboldt County, Cal. : Greatest length, 34.3 (33.5- 

 35); palatilar length, 13.5 (13.3-13.7); mastoidal breadth, 16.4 



(16.3-16.4); interorbital breadth, 

 8.1 (8-8.1); maxillary tooth row, 

 10.7 (10.5-10.9); mandibular mo- 

 lar-premolar row, 10.4 (10.3-10.5). 



Retnarlcs. — Judged by the speci- 

 mens examined, Scapanus orarius 

 (including the subspecies scJiefferi) 

 has a more extensive geographic 

 range than S. towns endii; it occurs 

 both farther north and farther 

 south, as weU as much farther east 

 (fig. 12). The ecological relation- 

 ship of the two forms is unknown; 

 its solution would involve most 

 valuable and interesting research 

 for some student favorably sit- 

 uated. 



The few specimens of S. o. ora- 

 rius available from the region of 

 the type locaHty are mostly of 

 young animals or have imperfect 

 skulls. However, there seems to 

 be very httle geographic variation, 

 either chromatic or cranial, in 

 specimens taken throughout the whole coastal strip extending from 

 Juan de Fuca to Mendocino County, Cal. 



Specimens examined. — Total number, 46, as follows: 



California: Crescent City, 3 ; Cuddeback, 1;^ Eureka, 6;^ Ferndale, 2;^ Mendo- 

 cino, 1;2 Orick, 1; Smith River, 1. 



Oregon: Astoria, 1;^ Myrtle Point, 1; Newport,!; Portland, 3;* Yaquina Bay, 4. 



Washington: Chehalis County, 1; King County, 1;^ La Push, 1; Neah Bay, 2; 

 Pacific County, 1;^ Port Townsend, 1; Puyallup, 6; Shoalwater Bay (type 

 locality), 2; South Bend, 5; Steilacoom, 1. 



1 Collection Mus. Vert. Zool., Univ. California. 

 zCoUection Field Mus. Nat. Hist. 

 3 Collection Univ. Michigan Mus. 



< Collection of H. E. Anthony, New York City. 

 6 Collection Milwaukee Public Mus. 

 8 Collection Amer. Mus. Nat. Hist. 



