254 PARASITES OF GIPSY AND BROWN-TAIL MOTHS. 



leaving the spot. The full-fed larvae seek the earth and, burrowing 

 well below the surface, construct a vaulted pupal cell, within which 

 the final transformation takes place during the late summer or fall. 

 The adult beetles remain quiescent and as a rule do not issue until 

 late in the succeeding spring. 



The breeding season coincides almost exactly with the caterpillar 

 season. The hibernated beetles begin egg deposition just a little 

 before the caterpillars are large enough to be easily found and attacked 

 by their young; the height of their activities in this direction is at a 

 time when their young are best provided for, and they cease oviposi- 

 tion very shortly after the gipsy moths themselves begin to deposit 

 eggs for a new brood. Very shortly thereafter, with summer still 

 at its height, the adult beetles, both male and female, burrow deep 

 into the soil and become dormant, awaiting the arrival of another 

 spring. 



The data as given above concerning the life and habits of Calosoma 

 sycophanta have been accumulated by Mr. A. F. Burgess, who has 

 had full charge of that part of the laboratory work which had to do 

 with the predatory beetles since the late summer of 1907. Up to 

 that time the pressure of other work was so great as to render impos- 

 sible any systematic studies along that or similar lines. The first of 

 the adult beetles of this species, together with a smaller quantity of 

 another, Calosoma inquisitor L., were imported and in part liberated 

 in the spring of 1906. A few were confined within the large out-of- 

 door cages of the type already figured and briefly described (see PL 

 XIV), and reproduction was secured in the instance of Calosoma 

 sycopJtanta. Neither Mr. Titus nor Mr. Mosher was able to give this 

 phase of the work the attention which it really deserved, and while 

 their observations were sufficient to cover most of the salient points 

 in the life history of the predator, there was still an abundance of 

 opportunity for further studies. 



In 1907 early and not very systematic surveys of the several field 

 colonies established by Mr. Titus the year before failed to result in 

 the recovery of the beetle. Accordingly, when similar experience 

 with others among the introduced insects had indicated that larger 

 colonies were likely to be required, it was determined to liberate all 

 the adult Calosomas in one locality as they were received from abroad, 

 and thus secure its establishment, if this were possible, before attempt- 

 ing further artificial dispersion. This was done, and several hundred 

 had been received and thus liberated by the time Mr. Burgess was 

 ready to take full charge of the work. 



Although it was quite late in the season, Mr. Burgess, with the 

 assistance of Mr. C. W. Collins, who has remained associated with 

 him ever since, succeeded in securing the eggs and in carrying to 

 maturity several larvae of the species in close confinement in jars of 



