180 NORTH AMERICAN FAUNA [No. 55 



weather he slept a great deal, but showed no signs of hibernation in 

 the coldest weather at Washington, down to 11 F. 



Breeding habits. The mammae in this as in other forms of the 

 group are arranged in 2 pairs of inguinal and 1 pair of pectoral, 

 and the number of young as shown by embryos noted in specimens 

 collected are usually 4, occasionally 5 or 6. A female carrying 4 

 embryos was taken at Klamath Falls, August 11, but throughout 

 the group embryos have been noted in April, May, June, July, 

 August, and September, probably indicating irregularity in the 

 breeding season, rather than numerous litters m a season. The ani- 

 mals are never very abundant and reproduction is apparently not so 

 rapid as in many other mice. 



Food habits. The names " grasshopper mouse " and " scorpion 

 mouse " have been applied to different subspecies of this group, be- 

 cause of their fondness for grasshoppers and scorpions, but in no 

 species is the diet limited to any one or even a few kinds of insects. 

 Insects and small animal life generally form most of their food, but 

 any kind of meat is eagerly eaten, and occasionally some seeds and 

 a little green vegetation are taken if their chosen food is not plentiful. 



During 2 years and more the captive from Oregon ate all the 

 grasshoppers of any species he could get, up to 20 individuals a day, 

 also crickets of many species, mole crickets, wild and domestic cock- 

 roaches, katydids, cicadas and their pupae, dragonflies, flies and fly 

 larvae and pupae, hornets, ant eggs and larvae, beetles of almost 

 every species offered including many large hard-shelled species, May 

 beetles, snap beetles, lady beetles, cotton-bollweevils and other 

 weevils, potato beetles, and such larvae as are commonly called 

 " grub worms ", " cutworms ", " corn worms ", and " wireworms ", a 

 great variety of moths and butterflies and their larvae, and cater- 

 pillars of the smooth kinds. He would eat angleworms but did not 

 care much for them. He was very fond of scorpions, especially the 

 large fat ones in southern Arizona, where he spent one winter, and 

 also of the large praying mantis there. He refused ants, myriapods, 

 blister beetles, hairy and spiny caterpillars, and slugs. 



Lizards and salamanders were killed and eaten but were not much 

 relished. 



He killed and ate white-footed mice, house mice, pocket mice, and 

 meadow mice, enjoying especially the newly born young meadow 

 mice. Some of the mice killed were approximately of his own size 

 and were nearly eaten in one night. The meat of larger animals, 

 such as chipmunks, ground squirrels, and kangaroo rats, and of small 

 birds, and even of a phalarope and a prairie falcon, was eaten, also 

 beef, mutton, chicken, or any meat offered. If fresh meat was not 

 available, he would eat cooked meat of almost any kind, and de- 

 lighted in a chop bone to gnaw, putting his feet on it and tearing at 

 it much as would a little dog on a large bone. Later, when from 

 lack of his favorite foods he was fed mainly on rolled oats, sun- 

 flower seed, and hempseed, he grew fat and lazy and lost his appetite 

 and much of his hunting spirit. When given the freedom of the 

 kitchen every night for a month or more, he cleaned out the cock- 

 roaches until no more could be found except a few that lived on the 

 shelves and did not come down to the floor. 





