76 CALOSOMA SYCOPHANTA. 



It also became apparent that many of the larvae passed through the 

 molting process on the trunks of trees, under burlaps, or among 

 masses of caterpillars or pupae of the gipsy moth. Later observations 

 showed that this was a quite constant habit and in the years which 

 followed it was made use of repeatedly as a means for determining the 

 dispersion of this insect. 



In 1908 plans were made to follow up the colonies more closely than 

 had been clone the previous year, and as the larvae of this species had 

 showed an inclination to secrete themselves under burlap bands 

 where caterpillars were more or less abundant, it seemed advisable 

 to burlap a number of trees in the center of each colony, so that con- 

 ditions could be easily determined by occasional examinations of the 

 burlaps during the summer. The plan was adopted of burlapping 

 from 50 to 100 trees in each colony. The field work in these colonies 

 was carried on by Mr. John V. Schaffner, jr., and Mr. F. V. Learoyd, 

 and during the summer beetles or larvae were found in all of the col- 

 onies except the one planted at Winchester. As it seemed desirable 

 to continue this work after the larvae had descended into the ground 

 to pupate, and as very accurate results can be secured by searching 

 for molted skins on the tree trunks, several weeks were devoted to 

 this work. About the middle of July Mr. Learoyd was detailed to 

 other work and Mr. Emory A. Proctor took up the field work hi his 

 place. As a result of these examinations it was also possible to trace 

 the dispersion of the species in a limited way. 



In 1909 the field examinations were carried on in the same manner 

 by Messrs. Schaffner and Proctor, and late hi the summer they were 

 assisted by several other men employed at the laboratory. The 

 results of the early summer inspection showed that the beetles 

 existed in aU of the colonies released in 1906, with the exception of 

 one at Winchester. Of the total number of colonies placed in the 

 field, 75 per cent were found to be reproducing. The results of the 

 late summer inspection — that is, where the distribution of a species 

 was determined by the presence of molted skins on the trees — is 

 shown on the accompanying map (PL IX) . This indicated a very 

 encouraging increase and spread of the insect. The method of 

 carrying on this work was to examine areas immediately outside of 

 the beetle colonies which were badly infested with the gipsy moth, 

 and if the molted skins were found, more territory was scouted until 

 the outside limit of spread was reached. 



During 1910 this work was continued, the same men having charge 

 of the investigations in the field colonies. At the close of the work 

 80 per cent of aU the colonies planted showed reproduction and much 

 gratification was felt. Molted skins were found near the colony 

 planted in Winchester in 1906, which indicates hi all probability that 

 some of the insects in that colony reproduced. The results of the 



