480 



REPORT OF STATE GEOLOGIST. 



skull broad, depressed and strong, with straight post-orbital proc- 

 esses ; first premolar nearly as large as the second. 



The range of this genus includes most of the north temperate 

 zone. The species are not numerous, however, and only one is 

 found in the eastern United States. 



MARMOTA MONAX (Linnaeus). 

 WOODCHUCK; GROUND HOG. 



Mns nioiiax Linnaeus, Syst. Nat., ed. 10, p. 60, 1758. 

 Arctomys monax Evermann and Butler, Proc. Ind. Acad. Sci. 



for 1893, p. 128, 1894. 

 Marmotta monax Allen, Bull. Amer. Mus. Nat. Hist., Vol. 16, 



p. 17, 1902. 



Diagnostic characters. — The woodchuck cannot be confused with 

 any other Indiana mammal. Its grizzled, yellowish gray color, 

 heavy body, broad, blunt head and short tail readily distinguish it 

 from all the mammals of the region. 



Description. — The predominating color of the head is dark 

 brown, this color being grizzled with paler tipped hairs. The edges 

 of the ears and some spots about the eyes are also paler ; a whitish 

 line borders the mouth. The hairs of the back and sides are ringed 

 with silvery gray, blackish and reddish brown. Belly generally 

 rather light reddish brown, often somewhat grizzled. The hairs of 

 the belly are usually scanty so that the skin is visible. The feet are 

 black or dark brown. Tail short and rather scantily haired, the 

 hairs usually having less of the silvery gray band of color and hence 

 the tail is darker than the back. There is a great variation in color, 

 some animals being nearly black and others much more red or gray. 

 I have also heard of all)inos, but have never seen any. 



Measurements. — The size varies greatly. Woodchucks usually 

 appear very much smaller in the spring than in late summer, when 

 they are fat and strong. An adult female from the Kankakee 

 Valley, the largest specimen of which I have any measurements, 

 though probably not the maximum size of the species, had a total 

 length of 615 mm. (24y2 in.) ; tail, 145 mm. (5 13/16 in.) ; hind 

 foot, 93 mm. (3 12/16 in.). 



Skull and teeth. — The skull (figs. 3 and 7) is characterized by 

 its very broad flat top, or dorsal, surface and angular outlines. The 

 incisors are long and broad ; the lower jaws are very imperfectly 

 fused together and r(»adily come a])ar1 in the clc^aned skull. Not 

 infrequently in the living animal they become slightly dislocated, 

 the upper incisors do not meet the lower ones exactly and both con- 



