[27] 



Report of the State Extomolooist. 



169 



nakedness, appearing as if dead, which undoubtedly some of them 

 were, as the result of previous defoliation. The elevation above tide 

 of Lake Pleasant is 1,800 feet. 



No information could be obtained of residents of the time when the 

 injury to the larches had first been noticed. To many it seemed quite 

 new when their attention was at this time called to it, although it 

 might probably have been observed during the two or three preced- 

 ing summers. 



Very few of the larvae were to be found on the trees on the nineteenth 

 July, and as most of these were apparently but about half-grown and 

 of a pale green color, as if recently molted, it is not improbable that 

 they were belated, sickly, or parasitized individuals which were des- 

 tined not to attain maturity. 



Not all of the larches in the vicinity had been wholly stripped. A 

 large one of eighteen inches in diameter at three feet from the ground 

 and reaching upward to a height of at least seventy feet, standing 

 alone in a pasture lot, and throwing out long and thick branches, had 

 its foliage less than one-half eaten. From a large number of larches 

 of a moderate height — of fifteen feet and under — that were entirely 

 free from harm, it appeared that the younger trees were not sought 

 by the parent saw-fly for oviposition. Whenever they had been eaten, 

 they were in the immediate vicinity of larger trees, which, having 

 been stripped, the migrants from them, in their search for food, may 

 have been able to ascend, with difficulty, in small numbers, such of 

 the smaller ones as chanced to be in their way. The tips of these 

 small larches, gave no evidence of oviposition in them. 



Cocoons. — Cocoons, in some instances only, were found underneath 

 the trees where search w r as made for them, but hot at all commensu- 

 rate with the immense number of larvae that had evidently been 

 present. Is it the habit of the larva to wander from the feeding- 

 ground to some distance in search of a favorable place for pupation ? 

 Do they leave the tree for the purpose at about the same time, after 

 the habit of some of the Lepidoptera, as, Datana ministra and CEde- 

 masia concinna; and if so, is this the explanation of the " migrations " 

 previously mentioned? Most of the cocoons collected were taken from 

 underneath moss growing around the borders and in cavities of rocks. 

 A large proportion — about ten per cent — had been eaten into at 

 one end and the larva consumed. 



Parasites and Enemies. — From the number of ants that were noticed 

 in association with the cocoons, it was thought that the credit for this 

 destruction might be due to them. With so active an enemy travers- 

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