THE GENUS CALOSOMA. 7 



in 1 square yard of leaf mold feeding upon the caterpillars that were 

 congregating there for pupation. Further observations were made 

 on August 21, which showed that as many as 80.2 per cent of the 

 pupae of H. guttivitta in one locality had been destroyed in the leaf 

 mold by the larvae of this beetle. 



Both adults and larvae of C. calidum Fab. search for their food on 

 and near the ground. The species of cutworms which are often 

 abundant during the spring and early summer furnish ideal food 

 for this predacious insect and large numbers are destroyed annually. 



Dr. A. W. Morrill has found that 0. peregrinator Guer. in both the 

 adult and larval stages is common as an enemy of the variegated 

 cutworm (Peridroma margaritosa Haw.) in Arizona, and the late 

 H. M. Russell of this bureau reported finding adults of C. semilaeve 

 Lee. at Hollywood, Cal., April 7 and 27, 1911, feeding upon the 

 larvae of Peridroma margaritosa under pea vines. This indicates that 

 the food habits of these two species of Calosoma are very similar to 

 those of C. calidum in both the adult and larval stages. 



Other data have been collected by various entomologists, and 

 many observations were made at the laboratory at Melrose Highlands, 

 Mass., most of which are given under the notes on each species and 

 indicate that great benefit must result from the work of these in- 

 conspicuous friends. 



ECONOMIC IMPORTANCE OF THE SPECIES OF CALOSOMA. 



The economic importance of Calosoma sycophanta has been set 

 forth in Bulletin 101 of the Bureau of Entomology by the senior 

 author 1 and more recently by both authors 2 in Department Bulletin 

 251, but since the former publication was issued other interesting 

 notes have accumulated and may well be added here. Dr. J. N. 

 Summers of this bureau, during the early spring of 1912, began a 

 careful study of the internal parasites of the brown-tail moth larvae 

 in a 4-acre sprout lot in South Lynnfield, Mass. In June it became 

 necessary to discontinue the observations owing to the depletion 

 by C. sycophanta of the larvae and pupae of the brown-tail moth. 

 The Calosoma beetles had consumed in some cases from 50 to 75 per 

 cent of the brown-tail moth pupae per tree or, as was figured later, 

 an average of 40 per cent for the whole area. 



Mr. W. F. Fiske, recently of the Bureau of Entomology, while 

 studying the gipsy moth and its parasites in Italy during the summer 

 of 1911, was afforded an opportunity of observing the efficient control 

 of the gipsy moth by C. sycophanta in a large forest. Mr. Fiske 

 states that there were" enough beetles in the forest at the time of his 

 visit to consume all the gipsy-moth pupae present, with the exception 

 of those hanging from the trunks of trees or limbs which could not 

 be reached by the predators. 



The beneficial work which is being done by this species of Calosoma 

 in New England through'its feeding upon the gipsy moth and the 

 brown-tail moth is now common knowledge in the section that has 

 been longest infested by these pests. 



i Bunress, A. F. Calosoma sycophanta. U. S. Dept. Agr. Bur. Ent. Bui. 101. M p. (p. 48), 9 pi., :?•: 

 fig. 1911. 



2 Burgess, A. F., and Collins, C. W. The Calosoma Beetle {Calosoma st/copluvita) in Now Kngkuul. 

 U. S. Dept. Agr. Bui. 251, 40 p. , 7 pi., 3 fig. 1915. 



