40 



SPKRMOPHILES OP THE MISSISSIPPI VALLEY. 



indicating that the ground squirrel had disposed of that many larvae 

 or pupae of ("nimbus within the given area. At another time I counted 

 fifty to the square yard. Evidently when sod worms are plenty the 

 ground squirrel is not an unmixed evil.' 7 (Ann. Eept. U. S. Dept. 

 Agriculture, 1887, p. 155.) 



Prof. 0. P. Gillette, in Bulletin No. 6 of the Iowa Experiment Sta- 

 tion, published in 1889, gives the results of the examination of twenty- 

 two stomachs of this spermophile, made at Ames, Iowa. The animals 

 from which the stomachs were taken were killed on various parts of 

 the college farm, and at intervals from April 19 to August 2. As a 

 result of this examination it was found that insects formed 46 per cent 

 of the stomach contents, with an average number of thirteen cutworms 

 and web worms in each. "The webworms in these stomachs were, in 

 the great majority of cases, the larvae of Crambus exsiccatus which is 

 very injurious to corn and grass in Iowa, its work in corn being very 

 often mistaken for that of cutworms.' 7 In conclusion it is stated that 

 "the insects which the squirrels feed on are almost exclusively in- 

 jurious species, chief among which seem to be cutworms, webworms, 

 and grasshoppers. As grass, clover, and other green stuff has been 

 abundant wherever the squirrels were taken, and as their stomachs 

 were often gorged with insects that must have given them much 

 trouble to catch, it would seem that they prefer the latter food" (page 

 242). 



In Bulletin No. 30 of the Agricultural College and Experiment Sta- 

 tion of Brookings, S. Dak., are given the results of an examination, by 

 J. M. Aldrich, of the contents of fifteen stomachs of the Striped Sper- 

 mophile. As relative amounts of the different materials found in the 

 stomachs are not given, it is impossible to compare the results with 

 those of other examinations. The stomachs were taken from animals 

 killed from June 19 to 23: " June 19 and 22, corn was well up, but the 

 planted kernels were still in condition to invite the gophers. There were 

 few ripe seeds of any kind, so that the stomach contents were generally 

 classified into insects, corn, and 1 green stuff, 7 the last being apparently 

 grass and other plants, a mixture difficult to analyze and not of great 

 importance from our standpoint. The corn was readily distinguish- 

 able, while the insects were usually represented by legs, antennae, 

 elytra, and other hard parts, more or less fragmentary. In the case of 

 cutworms and other larvae, the whole or a large piece of the skin was 

 generally found, the soft parts having been crushed out. It was not 

 possible, as a general thing, to make out the species of the insect, but 

 the genus or family is sufficient to indicate pretty well whether the 

 species is injurious or not. 



"Kos. 1 to 7 were killed on the afternoon of June 19 between 1 :15 and 

 4:30. 



" iVo. 1. — In the road near the corner of pasture. Only grass and 

 small grain in the immediate vicinity. Stomach quite full, mostly 



