408 PROCEEDINGS OF THE ACADEMY OF [185)8. 



decided, (1) whether the British Columbia Pocket Mice taken by me 

 are identical with the type of lordi. (2) If so, can they he identical 

 with mollipilosust (8) What is their relationship to P. montieola ot 

 Baird? (4) Are any of these the same as Cricetodipus parvus f (5) 

 To what faunal areas do these species belong? 



(1). To the first query I can answer without hesitation in the 

 affirmative. I cannot find the slightest discrepancy between Gray's 

 original description and the specimens from Vernon. This is further 

 confirmed by Mr. Oldfield Thomas's letter quoted by Dr. Merriam 

 in his remarks on lordi in American Fauna No, 1. 



(2). Perognaihus mollipilosus differs from lordi in the following 

 particulars: a, smaller size; b, tail one-third longer than head and 

 body; e, cinnamon tints; d, color of upper parts descending to 

 wrist ; e, it inhabits a different faunal region. Its only affinities to 

 lordi, so far as can be determined from Coues's description, consist 

 in the non-penicillate tail, soft and smooth pelage, white lower parts, 

 pale fulvous lateral stripe and bicolor tail. In lordi, however, the 

 tail is slightly crested- penicillate and plainly tricolor, the latter a 

 a peculiarity I have not noticed in any other murine rodent. 



(8). The characters of lordi coincide more closely with those of 

 P. montieola of Baird and Merriam than with any other. Mr. 

 Thomas wrote Dr Merriam, after examining the type of lordi in the 

 British Museum, that, "so far as (he could) make out from Coues's 

 description (it) is the same as P. montieola." 



The description of Cones referred to was made on the supposition 

 that a specimen from Fort Crook, California, was the same as Baird's 

 type winch is supposed to have come from St. Mary's Mission, Mon- 

 tana. Dr. Merriam refers to this Fort Crook specimen without 

 hesitation as mollipilosus, (Coues's provisional name for it), and says 

 the 7*. montieola of Baird "is a very different animal." We have 

 seen that lordi and mollipilosus are not synonymous, and Dr. Mer- 

 riam thinks mollipilosus and montieola are quite distinct, while Mr. 

 Thomas thinks the type of lordi answers Coues's hybrid description 

 of montieola et mollip'ilosus. 



As the description of montieola has several year's priority over 

 lordi the stability of the latter in our nomenclature depends on its 

 specific dissociation from montieola. That they are different species 

 I have very little doubt, notwithstanding their apparent resemblance. 



As compared with lordi, montieola may be distinguished by a, 



