40 



winter and until the middle of the following summer. Even the 

 modes in which the two larvae operate upon the apple are perceptibly 

 different. The Apple-worm burrows chiefl}' in the core of the 

 apple and the part immediately around the core, though it occasionally 

 makes an inroad upon the pulp, and often bores its way out through 

 the cheek of the apple. The Apple-maggot, on the contrary, so far 

 as I can find out from the statements of my correspondents and from 

 the specimens of infested apples sent me, never penetrates into the 

 core, but tunnels exclusively the flesh or pulp of the apple, making 

 therein little, rough, roundish, irregular and discolored excavations 

 about the size of peas; which, when several larvas are at work on the 

 same fruit, often run together, so as to render the whole a mere mass 

 of useless and disgusting corruption. 



This Apple-maggot Fly must be carefully distinguished from Dr. 

 Fitch's Apple Midge {Sciara mall,) previously referred to in connec- 

 tion with the Graj)e Midge. (See above, p. 32.) The whole Order 

 of Two-winged Flies (Diptera) — with the exception of the small and 

 very anomalous group comprising the Bird-flies (Ornithomyia) and 

 the Sheep-tick — is divided into two grand groups, one of which {Nein- 

 ocera) comprising the Musquitoes, Buffalo-gnats, Midges, Crane-flies, 

 etc., has long, many-jointed antenna in the Fly State; while the other 

 group (Brachyceraj) comprising the Horse-flies, the Syrphus flies, 

 many of which are cannibals, the parasitical Tachina flies, and several 

 families containing the JTouse-flies, Onion-flies, Cabbage-flies, etc., 

 has short antennae aparently composed of only three joints, and usu- 

 ally with a slender bristle growing out of the last. It is to the former 

 of these two great groups that Dr. Fitch's x^pple Midge belongs. It 

 is to the latter of these two great groups that my Apple-maggot Fly 

 belongs. They are therefore radically and fundamentally distinct. 



It only remains, in order to complete the History of this very 

 beautiful, but destructive species, that I should annex descriptions of 

 it in all its stages, so that for the future it may be scientifically recog- 

 nizable. A species of the same genus, not very unlike it in the Fly 

 state, {Trypeta solidaginis, Fitch,) produces a round gall or swelling 

 about the size of a hickory nut on the stem of a species of Golden-rod 

 (Solidago) inside which, any time in the winter and early spring, its 

 fat wJiite larva may be easily discovered reposing calmly in a little 

 central cell surrounded by white pithy matter. By placing some of 

 these galls, which are very common both in the East and in the West, 

 in any convenient vessel, the Fly may be easily obtained from them 

 as the spring opens. According to my friend Baron Osten-Sacken, 

 who has paid special attention to the Order Diptera,there is a Euro- 



