iNVESTiLiAiioN or i,ii''h: llls|•()l;^. 29 



An examination of this t!il)lc sliows that hirvse hatching hitc in 

 June transformed much more rapidly than those noted in Table 

 IV, the difTcrence in the total average length of time being 12] days. 

 Similar records based on a few experiments have been secured from 

 larvae that hatched at the laboratory late in July or during the first 

 few daj^s in August. The length of time spent in the larval stages 

 was longer than the time recpiired for the larvic hatching in June. 

 This is partly due to the dilliculty of furnishing an ample food supply 

 in August. 



TiMK ()!•' ArPEAHANCK OK THK LaUVA. 



The date of the first appearance of the larva of this species in the 

 field, of course, differs from year to year, depending on the season, 

 and in colonies that have been liberated larvae are seldom found 

 as soon as the first ones hatch and begin feeding. The records of 

 tliis investigation are rather fragmentary because of the relatively 

 small number of adults that have been liberated in field colonies 

 since the work ])egan, and owing to the tlillicidty of making frequent 

 examinations of any given colony and searching thoroughly enough 

 to find the small l;irva3. The earliest field records, however, are as 

 follows: 1907, July 17; 190S, June 29; 1909, July 7; 1910, June 27. 

 It should be stated that the first larva? found in 1907 were nearly 

 full grown, which explains partialh^ the reason for their being found 

 so late in July, although the season was not so early as that of the 

 two following years. The latest records which we have of finding 

 larva? in the field are as follows: 1907, August 7; 1908, July 8; 1909, 

 August 3; 1910, August 2. In the laborator}^, where food was more 

 abundant in early June and during the month of August than in the 

 field, it has Ijeen possible to rear larva? over a longer period of time. 

 Aside from the food' problem it has been possible to control to some 

 extent temperature and moisture conditions, so that the time during 

 Avhich feeding experiments have boon carried on has been prolonged. 



Hahits ok the Larva. 



Larvae of this species secure food by searching for the caterpillars 

 and pupae of various lepidopterous insects. Undoubtedly some of 

 those attacked are found on the surface of the ground or beneath 

 leaves or litter, where they have sought shelter either for protection or 

 pupation. The larvae of this species, however, in addition to feeding 

 in such situations are able to climb trees and devour their i)rey upon 

 the trunks or branches. To this extent they may be considered 

 arboreal in habit, although they are seldom found in any great 

 ({uantities on trees which have smooth bark, as it is cpiite necessary 

 for them to travel over uneven surfaces in order to secure a sure 



