Mar. 1899. MAMMALS OF THE OLYMPIC MOUNTAINS ELLIOT. 



257 



The figures exhibit the inferior surface of skull in natural 

 size, and the upper tooth row seven times enlarged. 





SUBGENUS MICROTUS. 



ii. Microtus macrurus. 



Microtus macrurus. Merr. Proc. Acad. Nat. Scien., Phil., 

 1898, p. 353- 



This large species was only procured by me on the banks of the 

 Elwah, and was not seen on the high mountains, so I concluded 

 it was an inhabitant of the low lands, possibly, indeed, also a lit- 

 toral form. But eight specimens in all were obtained, of which 

 three only were adult. They merely differed, however, in size, 

 and the young perhaps did not exhibit quite as grey a rump as 

 did the old individuals. This color, however, is only visible in 

 certain lights, and may probably be regarded as the sheen of the 

 grizzled buff and brown of the upper parts. None of the tails of 

 my specimens equal the length given by Dr. Merriam for his 

 type, the longest being 82 mm. This member, however, varies 

 greatly among individuals, as my examples prove. I should 

 judge that this is not a common species even in the localities it 

 frequents, or else it is very careful not to occupy itself with traps, 

 and although we endeavored to increase our series, were not able 

 to accomplish it. 



Eight specimens: Johnson's Ranch, Elwah River, 7; Boulder 

 Creek, i. 



The cuts show the under surface of skull, natural size, and the 

 upper tooth row, over six times enlarged. 



