No. 4.] GYPSY MOTH — APPENDIX. 415 



captured late in the evening, upon examination by Mr. 

 Kirkland were found to contain specimens of Calosoma 

 calidum intact, they having undoubtedly been swallowed 

 only a short time previous. Calosoma frigidum observed 

 in confinement has been found to feed at night as well as 

 during the day. These facts show that the members of this 

 genus under observation accomplish a great amount of good 

 by their nightly raids against injurious insects. 



Bearing in mind the fact that the gypsy moth caterpillars 

 feed at night and seek shelter during the day, and that these 

 beetles are active, climbing the trees at night, and are also 

 busy searching out food in sheltered places during the day, 

 we are led to believe that they are most valuable allies. 

 The feeding habits of the different species vary somewhat, 

 although all have been taken on the trunks of trees and 

 under burlaps during the day. As a rule the number of 

 gypsy moth larvee killed on the trees depends upon the size 

 and agility of the beetles. In point of etficiency they rank 

 in the following order: fricjidwm^ calidum and scrutator; 

 frigidum is most skilful in this respect, and has been ob- 

 served not only to feed on a vertical surface but to support 

 itself and feed on the under side of a horizontal branch. A 

 rise in temperature seems to stimulate their activity and the 

 desire for food. Specimens of Calosoma frigidum observed 

 in confinement during very hot weather were more active, 

 ate more and laid a greater number of eggs than when the 

 weather was cooler. When the temperature fell still lower 

 they sought the ground, ate very little and seldom laid 

 eggs. As far as observed, the members of this group de- 

 pend entirely on their well-developed legs as a means of 

 locomotion, although both sexes oi frigidum have been oli- 

 served to viljrate their hind wings in confinement, but wlien 

 thrown in the air they do not make the slightest efibrt to 



fly. 



Specimens of C. frigidum while confined in cages have 

 been fed, in addition to the gypsy moth larva?, pu})ai and 

 imagoes, the following caterpillars, which they ate freely : — 



Euvanessa antiopa^ Grapta progne ( ?), Protoparce celeus, 

 Hijphantria cunea^ Euchcetes egle, Halesidota caryve, H. 

 maculatay Orgyia definila (pupa also), O. leucostigma 



