1906.] Allen, Mammals from Western Mexico. 243 



are often smaller than in vigorous animals of the seventh to ninth 

 years. 



6. Sciurus poliopus cervicalis Allen. 



Sixty-nine specimens: Tuxpan, i specimen, June 24; Volcan de 

 Fuego, 61 specimens, July 5-31; Las Canoas, i specimen, Aug. 16; 

 Tanko Riparti, i specimen, Sept. 26; Los Masos, 5 specimens. 



The type of cervicalis was taken at Tonila, Jalisco, May 14, and 

 has the nape patch and the rump more fulvous and less rufous than 

 any specimen in the large series from Volcan de Fuego. A June 

 specimen from Tuxpan, however, closely resembles it. Nearly all 

 of the Volcan de Fuego specimens are in fresh pelage very dark gray 

 with the nape and rump patches very dark, often with only a little 

 rufous suffusion, but generally distinctly suffused with rufous. In 

 one specimen these patches are practically obsolete, they scarcely 

 differing from the rest of the dorsal surface. In two or three others 

 they are only faintly represented. In some specimens the lower 

 surface of the tail is almost entirely deep black; in a few examples 

 there is a slight mixture of yellow hairs along the median line of the 

 lower surface of the tail, in this respect showing a slight approach 

 to 5. p. colimcnsis of the adjoining coast region. 



The collector's measurements of 20 adult males average as follows: 

 Total length, 499 (477526); head and body, 253 (235266); tail 

 vertebrae 246 (230-266); hind foot without claws, 58.5 (5660); 

 hind foot with claws, about 66; ear from notch, 32 (3035): 18 females, 

 501 (489-518); 252 (235-267); 248 (235-261); 58 (54-60); 31 (29-32). 

 These measurements fall somewhat below those given by Mr. Nelson 

 for 5 adults, namely 536, [268], 267, and (hind foot with claws) 64 . 4, 

 a difference of about 36 mm. in total length, due perhaps to different 

 methods of measuring, but more probably to the fact that all of the 

 Volcan de Fuego series, young adults as well as adults, is here included. 



7. Sciurus poliopus tepicanus subsp. nov. 



Type, No. 25258, $ ad., Rancho Palo Amarillo, near Amatlan de Cafias, 

 Tepic, altitude 5000 feet, Jan. i, 1905; J. H. Batty. 



Top of head black varied with gray; nape patch a slight suffusion of pale 

 fulvous, varying in different specimens from nearly obsolete to well-marked; 

 rump patch similar but usually less distinct; rest of upper parts gray, much 

 paler than in S. p. cervicalis; tail above with the hair broadly ringe 1 subapically 

 with black, and with long white tips; tail below with the hairs narrowly ringed 

 with black and white, the white greatly prevailing; ventral surface white; 

 feet gray; ears mixed gray and fulvous, with the usual large white spot at the 



