FIELD BOOK OF INSECTS. 



New Jersey alone, I can do no more than give samples. 

 Acronycta americana (Plate LI) is one of our largest 

 species; the light-gray front wings expanding nearly 2.5 

 inches; the hind wings are brownish. With sufficient 

 imagination, you can see, near the hind, outer angle of 

 the front wings of americana and some other species, the 

 "dagger" which is responsible for the common name of the 

 genus. Americana' 1 s larva is one of the hairiest of Noctuid 

 larvae; with its dense, pale-yellow hairs it resembles an 

 Arctiid but the hairs are scattered over the body instead of 

 being grouped on tubercles as is the rule among the Arctii- 

 dae; there is a pair of long, black hair-pencils on the first 

 abdominal segment, another pair on the third, and a single 

 such pencil on the eighth abdominal segment; in addition, 

 there are hairs, longer than the general covering, along 

 the sides and at each end. It feeds on maple (its favorite), 

 elm, oak, and other forest trees. Larvae of this genus 

 often rest near the base of a leaf with the front end of the 

 body curved back so that they are somewhat fish-hook- 

 shaped. When disturbed, Acronycta larvae are given to 

 curling up and dropping off of. their food plant. They 

 pupate in loose cocoons, which are placed on rough bark 

 or under ground-debris. 



Acronycta hastulifera, according to its specific name, 

 "bears a spear" instead of a dagger. Its larvas are often 

 abundant on alder and have been recorded on maple; 

 they suggest those of americana but their color varies 

 from pale to deep chocolate-brown. Eliot and Soule, 

 whose Caterpillars and their Moths is not only a model of 

 careful work but also shows what pleasure and profit 

 ladies may get from a "crawlery, " point out that these 

 larvas "are subject to fungoid diseases which kill many of 

 them, and their stiff bodies may be found on branches of 

 the alders, apparently unharmed, but they break at a 

 touch and are filled with fungoid growth." As a matter 

 of fact, fungi and bacteria vie with insect parasites as 

 enemies of caterpillars in general. 



The larva of Acronycta hamamelis, as its specific name 

 signifies, feeds on witch-hazel but it is also found on 

 various forest trees. This larva differs from its two rela- 

 tives, just mentioned, in being almost hairless; it varies 



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