145 



' Adult specimens recently captured and placed together often kill and devour each 

 other, mothers even eating their young. 



" One evening I placed in a large cage two old males taken in different burrows. In 

 the course of the night much fighting and crying was heard, and the next morning one 

 was found to have been killed and partly devoured by his companion. The other was 

 supplied with corn and fresh beef, both of which he ate ; and in the course of the fore- 

 noon a half grown house mouse was placed alive in the cage. This, without provocation, 

 he at once attacked, as if in great rage, uttering his usual cry of anger, with his hair 

 erected and bristling. In fighting he sprung upon the mouse, striking with his fore- 

 feet, at the same time snapping quickly with his teeth, and then springing nimbly back. 

 Finally he seized the mouse by the rump with his incisors, and thus broke his back bone. 



ter this the latter, which had fought as well as he could, ceased to resist, when the 

 meadow mouse, catching him in his teeth, threw him forcibly to some distance, and con- 

 tinued to strike, bite and toss him about until he was dead. His anger then appeared 

 to subside as quickly as it had' risen, and in a few minutes he was observed placidly 

 eating corn. The old males were always very pugnacious, biting and striking at any 

 thing thrust at them. 



"When much teased in this way, they sometimes turned on their backs, snapping 

 with their teeth and striking with all their feet. 



" When enraged they uttered a low, harsh, creaking note, resembling very much that 

 of a young puppy. If hurt, their voices were clearer and sharper. Sometimes they 

 chattered their teeth in anger. The females were not so pugnacious, and were more 

 silent ; seldom crying out in anger, or fighting when teased. They were equally as car- 

 nivorous, however, as the males. 



" Like most Arvicolcs, this species takes to the water boldly, and swims and dives 

 readily." 



Sub-Genus Myonomes Rafinesque. 



< Arvicola of American writers. 



^^^Arvicola A, Hemiotomya, Baird, M. N. A., 1857, 515 (type, A. riparivs, 



Ord. 

 = Mynomes^ Eafinesque, Am. Monthly Magazine, ii, 1817, 45. 

 = Myonomes, Coues, Proc. Acad. Nat. Sci., Phila., 1874, 189. 



In Myonr.mes the back upper molar has two external triangles and a 

 posterior crescent. Middle upper molar with two internal triangles. 

 Front loWer molar with three internal and two or three external lateral 

 triangles. Ear unrimmed in front. Sole, 6-tuberculate. Fore claws not 

 longer than hinder ones. Tail, about one-third the head and body, or 

 more. Pelage, ordinary. Of maximum and medium size. 



Arvicola (Myonomes) ripakius Ord. 



Common Amkrican Meadow Mouse, 



1815. Arvicola pennsy'vanica, Ord, Guthrie's Geog., 2d Am. ed., ii, 1815, 

 292 (based on Wilson, 1. c.) — Wagner, Suppl. Schreb., viii, 588. — 

 10 



