316 

 CANIS LATKANS. 



The Coyote, or Prairie Wolf, the Dearest American affine ef the 

 Gray Wolf, is as remarkable for its constancy of character, especially in 

 respect to color, as the latter is for its variability. The individual varia- 

 tions in the color of Canis latrans consist generally in the depth or in- 

 tensity of the shadings of black or rufous that more or less pervade the 

 pelage of certain parts of the head and body. Although considerable 

 variations have been noticed in respect to the form of the skull, they 

 are small in proportion to those presented by Canis lupus. It is also 

 much less influenced apparently by locality. The species has, however, 

 a less extended range than Canis lupus, and the specimens at command 

 represent localities less widely separated than do the series of skulls of 

 Canis lupus. 



Measurements of forty skulls are given below, mainly from Nebraska, 

 Dakota, and Wyoming. The most distant localities are Columbia 

 Eiver and Fort Tejon, California, Southern Texas, and Fort Union, 

 Montana. Of this series of forty skulls, the average is 7.40; only 

 two attain a length of 8.00, one of which (measuring 8.00 in length) is 

 from Fort Union, and the other (8.05 inches in length) is from Fort Mas- 

 sachusetts, New Mexico. Only two fall below 6.95, one of which meas- 

 ures 6.65 and the other 6.50 ; the smaller being from the Coppermine 

 Eiver, New Mexico, and the other from Fort Kandall, Dakota. Of 

 thirteen specimens from Fort Randall, the largest measures 7.60 in length 

 and the smallest 6.65, the majority (more than three-fourths) falling 

 between 7.00 and 7.50, thus presenting a remarkable uniformity in size. 

 Ten others from Fort Kearney average fully as large, the extremes 

 being 6.95 and 7.60, while four-fifths of them fall between 7.00 and 

 7.50. Three specimens from Fort Tejon, California, measure respect- 

 ively 7.95, 7.60, and 7.45, or above the average of those from Dakota 

 and Nebraska! Four specimens from Wyoming Territory, however, 

 measure each 7.80. A single San Diego specimen measures 7.75, and 

 two specimens from Southern Texas respectively 6.95 and 7.00, or but 

 little below the average of northern specimens. Of four specimens 

 from New Mexico, three attain or exceed 7.40, one reaching 8.05 and 

 forming the lacgest of the series ; the other, with a length of only 6.50, 

 forms the smallest of the series, both the largest and the smallest being 

 from New Mexico. It thus appears that in Canis latrans there is com- 

 paratively little decrease in size southward, instead of the southern 

 averaging fully 25 per cent, smaller, as is the case in Canis lupus. The 

 difference between the extremes is only 1.55, or about 20 per cent., against 

 twice that amount in Canis lupus. Throwing out the two skulls that fall 

 below 6.95 would reduce the difference between the extremes to 1.10, and 

 the variation to only 15 per cent, of the average ! In both Canis latrans 

 and Canis lupus, the width of the skull averages about one-half the length, 

 ranging in Canis latrans from 0.49 to 0.52, while in Canis lupus the range 

 in this proportion is from 0.48 to 0.56. 



A glance at the table shows that while the Upper Missouri specimens 

 are rather younger than those from Fort Kearney, they rather exceed 

 them in size, and the difference would be somewhat greater if they were 

 of strictly corresponding ages. The single very large skull from New 

 Mexico is also that of a verv old individual. 



