The Food Relations of the Carabidce and Coccinellidce. 45 



Genus Amphasia, 



Four examples of A. interstitialis indicated that this species is 

 almost strictly vegetarian, only three per cent, of the food con- 

 sisting of insects. Of the remaining ninety-seven per cent., little 

 can be said except that it was certainly of vegetable origin. 



Genus Bradycellus. 



A single specimen of Jj. dic/woas had eaten only insects, which 

 could not be further classified.* 



Genus Harpalus. 



Nineteen specimens of Harpalus were studied, belonging to 

 the three species caliginosus, jDewwsy/yawic^s, and herbivagus. 

 Two individuals belonging to the first of these species, from 

 Normal and Towanda in August and September, had taken about 

 one-tenth of their food from insects (caterpillars and Diptera). 

 Twenty per cent, of unrecognizable animal food and five per cent, 

 of mites bring the general average up to thirty-five per cent. 

 The sixty-five per cent, of vegetation eaten consisted chiefly of 

 tissues of grass. A little pollen of Composita?, and other exogen- 

 ous structures were likewise recognized. Three per cent, was 

 fungi, all spores of Helminthosporium. Seven specimens of H. 

 pennsylvanicus, caught in Northern, Central, and Southern Illi- 

 nois, in April, August, and September, had taken about one per 

 cent, of their food from the animal kingdom. This included an 

 ant eaten by one of the beetles, and a few mites taken by another. 

 About half the vegetable food was not further recognizable. 

 Twenty-nine per cent, was the pollen of rag-weed, taken by two 

 beetles captured upon that plant, and fourteen per cent, was 

 derived from June grass. Fungi made eight per cent, of the 

 food of these beetles, a little of it Helminthosporium, but chiefly 

 Peronospora. Three examples of H. herbiix/f/us, taken in North- 

 ern Illinois, had eaten only vegetation, about one-third of it, 

 graminaceous, and another third fungi. Only seven per cent, of 

 the food'of the above twelve specimens of this genus, taken from 



*Mr. Webster reports a specimen of B. rupri^fris taken in 1881 in 

 the act of devouring an earth-worm. 



