TWO INSECTS OF THE ORCHARD — SNODGRASS. 



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face. Two little, black, featherlike tufts project from the shoulders, 

 and on the middle of the back of the closed wings is a large black 

 spot. 



The first part of May is the usual time of emergence in southern 

 New England and in New York State, with the date earlier farther 

 south. The female moths lay their eggs on the leaves, usually on the 

 under surfaces (pi. 2, E) but sometimes on the upper. Each egg (F) 

 is a tiny, flattened, elliptical object of a pale greenish tint closely re- 

 sembling that of the under side of the apple leaf, where it is gener- 

 ally placed close to a midrib or one of the larger veins, well concealed 

 amongst the tangled leaf hairs. The writer made no record of the incu- 

 bation period, but others have stated that the eggs hatch in from 

 6 to 10 days. The young caterpillars are born with the instinct of 

 miners and burrow directly through the bottoms of their eggs into 

 the tissue of the leaf. Here each eats out a mine as does the young 

 shield-bearer, only the mine of the 

 young Bucculatrix is a winding 

 tubular gallery (pi. 2, G, c) grad- 

 ually enlarging as it lengthens. 

 The mines might be mistaken for 

 those of the serpentine leaf miner 

 (fig. 5, A), except that they never 

 reach the length that these mines 

 do. and they can usually be identi- 

 fied by a dark, purplish red dis- 

 coloration of the leaf immediately 

 about them. The young caterpil- 

 lars feed in the leaf only about 

 eight days, when the mines attain a length of one-half or three- 

 fourths of an inch. Then the caterpillars leave the mines through a 

 slit cut at the larger end. usually on the upper side of the leaf, but 

 occasionally below. 



When the young Bucculatrix caterpillar leaves its mine it is ready 

 to molt, but it still feels the need of protection and proceeds at once 

 to build a special molting tent on the surface of the leaf. It is not 

 evident why it does not do the easy thing and shed its skin in the 

 mine before emerging, but Bucculatrix is an individualist and in- 

 sists on its own way at any cost. Selecting a small depression any- 

 where on the leaf, a favorite spot being at the very tip where the 

 edges curl up slightly, it lays down a thin carpet of silk against the 

 surface and then weaves over this a flat canopy sewed fast all around 

 the edges but with a round hole in the center. The caterpillar now 

 crawls into the tent through the hole in the top (fig. 10) and closes it 

 with a webbing of silk spun from the inside, often laying on so 



Fig. 10. — A Bucculatrix caterpillar enter- 

 ing its molting cocoon on the surface 

 of a leaf. 



