PREDACEOUS BEETLES. Ill 



ter, while the remainder was of vegetable origin. Of the 

 animal matter, '20 per cent, could not be identified, 10 per 

 cent, consisted of insect food, caterpillars and Diptera being 

 represented, while the remaining 5 per cent, were mites. 

 The vegetable food consisted chiefly of the tissue of grasses 

 and a little pollen from flowers belonging to the family Com- 

 posite. In addition to the above, the spores of a fungus 

 (Helminthosporium) amounted to 3 per cent. This shows 

 conclusively that vegetable food is taken freely during this 

 time of year. The fact that the beetles eat such vegetable 

 matter as pollen, seeds of common weeds and spores of fungi, 

 should be counted in their favor rather than against them ; 

 and if they are able to subsist on such food during the season 

 when caterpillars and noxious insects are scarce, it is in- 

 deed a wise provision. If, however, subsequent observa- 

 tions and investigations show that they actually feed to any 

 irreat extent on wheat or other vegetable matter of economic 

 importance, we shall be led to believe that their usefulness 

 has in the past been over-estimated. 



September 20 a pair of H. caliginosus was received from 

 Mr. F. H. Mosher, an inspector of the Board. They were 

 placed in a breeding jar with a larvse of Halesidota maculata 

 and flower head of ragweed. Another female found near the 

 insectary was placed in the jar three days later. The beetles 

 fed on the weed, eating chiefly the seeds, but did not molest 

 the caterpillars. A pair copulated the following day, re- 

 maining in coitu about three minutes. They were then 

 isolated, and two days later, September 26, seven eggs were 

 found about three inches below the surface of the ground. 

 Two eggs were deposited the following day, and on October 

 15, no more having been laid, the beetles were placed in a 

 wire cage near the insectary, to obtain notes on their hiber- 

 nation. The eggs, which were kept in the insectary, hatched 

 in nineteen days from the date of oviposition. Some of 

 these larvse have also been placed in an outdoor cage for the 

 winter, and an attempt will be made next year to complete 

 the life history of this species. 



