MAMMALS OF THE MEXICAN BOUNDARY. 353 



respectively, present color characters intermediate between those of 

 the young of the year and the adult. 



Summer -pelage of adult (adult male No. ||||, coll. Anier. Mus. Nat. 

 Hist., New York, taken at Fort Verde, Arizona, August 16, 1884).— 

 Upper parts pale reddish fulvous, much paler and more uniform than 

 m any winter specimen. 'A darker vertebral area is indicated. The 

 rump and upper side of the tail are considerably paler and more yel- 

 lowish than in winter. The long hairs of the sides, giving the general 

 body color, are paler yellowish fulvous; and the same shade prevails 

 on the under parts, where the overhair is very scanty. Along the 

 middle of the belly is a band of dark, shining chestnut, a paler, barely 

 apparent shade of which extends forward to between the fore legs 

 and more distinctly backward to the vent. The under side of the tail, 

 posterior to the anal orifice, is reddish chestnut, paler than the dark 

 area of the middle of the belly. The bare sole of the hind foot is 

 fringed behind the heel with a band of long, chestnut-red hairs. The 

 upper surface of the hind feet is covered with coarse hairs of a dark 

 vinaceous color, with a few markings of fulvous, especially upon the 

 terminal portion of the toes. The front, sides, and under surface of 

 the head and the fore legs and feet are a paler shade of fulvous than 

 the rest of the body; and the feet are marked above with a few irreg- 

 ular vinaceous blotches (mixed with brown) similar to, but paler 

 than, those of the hind feet. The soft underfur is dark, grayish 

 brown on the upper parts, becoming pale grayish on the under parts. 



Very young specimens, taken in June, have a drabish coloration. 



Remnrks. — The beaver of Canada and the northeastern United States 

 ( Castor canadensis canadensis) is of a beautiful glossy bay on the upper 

 surface, paling to chestnut on the head and rump. The under surface 

 is seal brown. Sometimes the color is still darker, the back being 

 blackish brown, the caudal peduncle burnt umber, and the under side 

 of head vandyke brown. The feet are seat brown. I hav'e examined 

 thirty-three skulls and a large number of skins of C. canadensis fron- 

 dator, from Arizona and Sonora. In old males the total length reaches 

 1,130 mm., and the bare and scaly portion of the tail measures 285 by 

 155. Adult males weigh 60 pounds and upward; females 40 to 50 

 pounds. 



Beavers are found throughout the Kio Grande Valley, except where 

 civilization has caused their disappearance. At El Paso I bought 

 some beaver traps from a trapper, but was unable to catch any bea- 

 vers. Some were living on Las Moras Creek, near Fort Clark, Texas, 

 but they also eluded me. Not having obtained a specimen, I can not 

 say whether the Texas beaver is most like Castor canadensis caroli- 

 nensis Rhoads or the present subspecies. Skins of the Arizona beaver 

 make elegant rugs, robes, and even fur trimmings when the long over- 

 30639— No. 56—07 m 23 



