190 NORTH AMERICAN FAUNA [No. 55 



Food habits. About all that is known of their food is from exami- 

 nation of the stomachs, which usually contain a combination of green 

 vegetation, seeds, or grain. Grass stems are found cut in short sec- 

 tions on their feeding grounds, and their abundance in and around 

 alfalfa fields would imply a fondness for the green leaves and tender 

 shoots of these plants. They are always eager for rolled oats used 

 as trap bait, and their very small stomachs indicate a diet of rich 

 food, more seeds than green vegetation. 



Economic statics. Too small and well hidden to be much noticed, 

 these little harvesters of the meadows often become very numerous 

 in the most fertile fields and meadows, where they take a small toll 

 of the forage and a share of the seeds. Their depredations seem 

 never to be noticed, but added to those of several other species of 

 rodents help to swell the total of serious losses. 



Clean fields, meadows, ditch banks, and borders would leave them 

 exposed to overhead enemies and be by far the most economical and 

 effective method of preventing their overabundance and possible 

 mischief. 



REITHRODONTOMYS MEGALOTIS LONGICAUDUS (BAIRD) 

 CALIFORNIA HARVEST MOUSE 



Reithrodon longicauda Baird, Mammals North Amer., p. 451, 1857. 



Type locality. Fixed at Petaluma, Calif. No type designated. Type series 

 collected by E. Samuels in 1856. 



General characters. 'Size, color, and general appearance much as in the com- 

 mon house mouse, but structural characters widely different; upper incisors 

 deeply grooved; tail well haired and not tapering noticeably; ears larger and 

 more hairy. Upper parts rich buffy brown, darkened with dusky along median 

 line of back and clearing to buffy orange along sides; feet, lower half of tail, 

 belly, and chin light gray or whitish ; breast buffy orange. 



Measurements. Average of a series of typical adults : Total length, 139 mm ; 

 tail, 73; foot, 17; ear (dry), 12. 



Distribution and habitat. From a range covering practically the 

 whole of western California these little mouselike rodents extend into 

 southern Oregon in the upper Rogue River Valley (fig. 39). There 

 are specimens from Grants Pass, Slate Creek (20 miles southwest of 

 Grants Pass), and Ashland. They undoubtedly occupy the whole of 

 the upper Rogue River Valley and" connect in range with those of the 

 Klamath Valley over the low ridge east of the Siskiyou Mountains 

 and grade toward the paler meoalotis in the Klamath Lake basin. 

 They are mainly in Upper Sonoran Zone. 



General habits. Usually these little animals are found in 

 meadows, on grassy or weedy uplands, or along weedy fence rows 

 bordering fields. In dry seasons they gather on the low moist 

 grounds, and even in wet marshes, but with the fall rains spread out 

 over higher country. They live as do the meadow mice under the 

 protecting cover of dense vegetation and make tiny runways over 

 the ground and numerous little burrows below the surface. Their 

 nests are usually placed on the surface of the ground, neat little 

 balls of grass with soft lining. 



Breeding habits. The females have normally 3 pairs of mammae 

 2 inguinal and 1 pectoral on 4 distinct mamary glands. The young, 



