THE CROW AND ITS RELATION TO MAN. 17 



and larvae are inveterate enemies of caterpillars, some species even 

 climbing trees in search of their prey. The offensive odor and sup- 

 posed warning coloration, especially of C. scrutator, C. willcoxi, and 

 C. calidum, appear to have no deterring effect upon the crow, the 

 nestlings of which ate even greater numbers than the parent birds. 

 The brilliantly colored C. scrutator was identified in 16 stomachs of 

 adults, six being the largest number found in any one stomach. The 

 fiery hunter ( G. calidum) was eaten more frequently, being present in 

 53 of the 1,340 stomachs. In one stomach, that of a bird collected in 

 New York in June, were the remains of at least 15 of these beetles, 

 forming half the bird's food. Another crow from New York had 

 taken 10, and one from Manitoba, 5. Four other species of Calosoma 

 were identified, but in none of the stomachs did they occur in large 

 numbers. 



Beetles of the less common genera Carabus and Cychrus were found 

 in correspondingly fewer stomachs. The large, broad ground beetle 

 Pasimackus, so common in some of the prairie regions of the West, 

 was a regular article of food of crows collected in Kansas. One of 

 these taken in May had eaten 16, while another secured in Illinois in 

 November had devoured no less than 80 of the larvae. Of the 1,340 

 adult crows, 57 had fed on Pasimackus. Both the larger and smaller 

 Scarites (S. substriatus and S. subterrane'us) were found, though 

 seldom more than one to a stomach. Of the smaller active ground 

 beetles with predacious habits those of the genus Pterostickus ap- 

 peared most frequently, but never in large numbers. Evarthrus ap- 

 peared in numerous stomachs from Kansas. Various species of 

 Harpalus also were well represented, especially the large H. caligi- 

 nosus, and H. pennsylvanicus, one of the commonest of the genus. 



The extreme abundance of members of the genus Amara in some 

 sections of the West would seem to indicate that they are more her- 

 bivorous than is generally supposed. A crow collected at Aweme, 

 Manitoba, in May had eaten no less than 176, along with several 

 Harpalus; another taken in April made away with 131 Amara, 

 6 Platynus, and fragments of a few other ground beetles; and a 

 third had its stomach nearly half filled with the remains of 91 

 Amara, 57 Harpalus, and 2 Calosoma calidum. Several other stom- 

 achs collected in the Northwest contained upward of a score of these 

 small beetles. Ground beetles of the genus Cklcenius, insects which 

 frequent damp situations, occurred in a number of the stomachs of 

 Kansas crows. Agonoderus pallipes, which is at times destructive to 

 seed corn, was present in only a few. 



In the destruction of predacious ground beetles, especially the 

 larger ones, as Calosoma and Pasimackus, the crow is doirfg man 

 indirect harm. Fortunately the quantity of such food is small, only 

 14653°— 18— Bull. 621 2 



