THE GENUS CALOSOMA. 11 



more information on this subject a series of experiments was conducted 

 by the junior author using captive skunks, foxes, and raccoons. 

 The results of these experiments are given in a following paragraph 

 and indicate that the skunk will feed freely upon these insects. 

 Field observations in 1913 have confirmed the experimental results 

 referred to above. In many sections of the territory infested by the 

 gipsy moth where C sycophanta has become abundant, unquestion- 

 able evidence was secured that skunks were destroying them in large 

 numbers. In some cases it was possible to find the ground thor- 

 oughly uprooted over considerable areas, which indicated that these 

 animals had been digging to secure beetles which were beneath the 

 surface of the ground. In addition to this, large amounts of excre- 

 ment were obtained, which showed that these beetles formed a large 

 percentage of the food of the skunk. (PL IV.) In some cases it 

 would appear that the work of this animal during the past year has 

 been sufficient to retard seriously the increase of this beneficial 

 species. 



In June, 1912, a series of observations were made by Mr. Mosher in 

 woodland near Melrose to determine whether birds were feeding 

 upon Calosoma beetles. For some time previous it had been noted 

 that along paths and wood roads a considerable number of wing- 

 covers and parts of beetles were frequently seen. Although Mr. 

 Mosher did not actually see birds feeding upon the beetles, he did 

 observe many specimens of the towhee or chewink (Pipilo erytroph- 

 thalmus) in the woodland and saw one devouring a female specimen 

 of Prionus laticollis. In the attempt to consume this insect the 

 elytra were separated from the thorax and the eggs and internal 

 tissues were eaten. As most of the hard parts of the insect were 

 rejected, it is fair to assume that this bird may have attacked Calo- 

 soma beetles in the same manner. 



The brown thrasher (Toxostoma rufum) has a somewhat similar 

 feeding habit and may be considered a possible enemy of these 

 beetles. 



During the summer of 1913 observations were made by Mr. J. V. 

 Schaffner, jr., and Mr. A. M. Wilcox, of the Bureau of Entomology, 

 which indicate that the crow is an enemy of Calosoma adults. One 

 of these birds was observed to seize a beetle and to convey it to its 

 nest in a near-by tree. Several parts of beetles were found at the 

 base of this tree and on examining the nest, which was occupied by 

 young crows about 3 weeks old, five broken and torn beetles were 

 found. 



Among the insect enemies of Calosoma are the predacious bugs, 

 although only a few records are available to support this conclusion. 

 On July 7, 1910, Mr. Schaffner observed a nymph of Pod is us sp. 

 feeding upon a second-stage larva of Calosoma sycophanta at Brook- 

 line, Mass. During each season several different species of Podisus 

 are found in Massachusetts, although they are not ordinarily abund- 

 ant enough to destroy many insects. 



In 1896 Mr. Burgess reared several tachinid flies from an adult of 

 Calosoma calidum. These were determined by the late D. W. Coquil- 

 lett as Pseudatractocera calosomae Coq., a species which he had reared 

 some years previous from C. peregrinator Guer. in California. Since 

 that time this species has been classified under the name Biomyia 

 georgiae B. & B. 



