800 Universifij of ('alifor)iia ruhlicafions in Zoology. [Vol.7 



yellowish of the neck and region in front of the forelegs en- 

 croaches on it in the San Jacinto animal. The dorsal coloration 

 is practically identical (slightly darker in the female) in the 

 two Nevada specimens, being of a uniform shade approximating 

 Vandyke brown. The southern California animal is much paler. 

 The upper lip in the Pine Forest Mountain animals is white all 

 around, as given by C. H. IMerriam for arizoncnsis (1896, p. 

 22). But there is no white in the San Jacinto animal except for 

 a good-sized patch just dorsal of the corner of the mouth. This 

 specimen, as stated by Merriam for Sierran animals, shows a 

 tendency to approach xantliogenys. There is a broad streak of 

 white on the sides of the face reaching up to a line drawn back 

 from the corner of the eyes, and a white area between the eyes. 

 These two marks are lacking in the Nevada specimens. All three 

 animals exhibit the small size which is said to be characteristic 

 of specimens of arizonensis from the Sierras as compared with 

 those from the Rocky IMountains. The female animal from 

 Nevada has a longer tail than either of the males, although both 

 of the latter are larger in every other respect. 



Distribution. — The species arizonensis is probably quite 

 generally distributed in the Transition zone of the Pine Forest 

 Mountains. We were unable to obtain evidence of the presence 

 of the animals in Upper Sonoran though this would necessarily 

 be implied by Bailey (1908, p. 30), who includes the mountain 

 weasel in his list of mammals of the arid interior. The present 

 records .show that in all probability Great Basin mountain ranges 

 having the Transition zone represented on their slopes will be 

 found to be inhabited by this species of weasel, so that the geo- 

 graphic distribution of arizonensis, instead of being the Sierra 

 Nevada and Rocky ]\Iountain systems only, will include isolated 

 mountain ranges (and prol)ably nearby plains to some extent), in 

 the Great Basin also. 



Habits. — Weasels were several times observed at the head of 

 Big Creek (altitude 8000 feet). They appeared only in the 

 early morning or late evening, and were apparently attracted 

 to the vicinity of our camp by the bodies of birds and mammals 

 which had been thrown out after skinning. Commonly the ani- 

 mals were seen among the logs in the immediate vicinity of the 



