THE AMERICAN ENTOMOLOGIST. 



49 



therefore lie was philosophically a far more in- 

 teresting object than the poet Pope, who 

 weighed only about a hundred pounds! As if 

 a sunflower was more deserving of our admira- 

 tion than an orange blossom ! As if we ought 

 to make a pet of a vulture rather tliaii^of a 

 mocking-bird! 



The Willow-ef,'!r Gall. 



(Salicis oi'um, "Walsh). 



On examining particular bushes of the Heart- 

 leaved Willow in the middle of the summer, 

 and especially such as seem to be in a diseased 

 and stunted condition, it will be noticed that 

 many of the twigs have one or more round or 

 oval swellings, from one-tliird to one-half an 

 inch in length, projecting from their sides, such 

 as are shown in Figure 31. If wc cut into these 

 swellings in the summer, their internal sub- 

 stance will be fonnd to be whitish and fleshy 

 like that of an apple; but [Fig. 31] 



by the autumn the apple- 

 like pulp is converted into 

 a reddish-brown sponge ^^^ 

 with many transverse fis- ^HJi 

 sures at right angles to the ^^S: 

 axis of the twig. By dis- '^W 

 secting down at any time 5 

 to the original surface of 

 the twig, a longitudinal 

 slit will be discovered, ^rrrrrrrT^rrQ 



about one-iifth of an inch i . 



long, manifestly produced ^ 



by the saws of the female 

 Sawfly that generates this 



gall. This species of Saw- 



- . . ,, . , Colors— Green, with piile- 



fly comes out in the mid- brown scales. 



die of the preceding April, and produces 

 the future gall by depositing in the slit which 

 she has cut with her saws a single egg, ac- 

 companied by a drop of the peculiar poi.?on 

 secreted by each species of gall-producing 

 Saw-flies. If one of these swellings, known 

 as the Willow-egg gall, is cut into about the last 

 of August, the larva that has hatched out from 

 the egg will often be found imbedded in the slit, 

 and already more than one-tenth of an inch 

 long, of a pale-yellowish color, with three pairs 

 of true legs and seven pairs of pro-legs, and a 

 very pale dusky head having the usual lateral 

 dark eye-spots. At this date, and even as late 

 as the first week in the succeeding March, many 

 full-sized galls will be found to be still solid 

 and uneaten by any larva, no doubt from tlie 

 egg having failed to hatcii out ; thus proving 

 that it is the drop of poison deposited along 



with the egg by the mother Sawfly, and not the 

 action of the jaws of the young larva produced 

 from the egg, that generates the gall. About 

 the middle or latter end of the April of the fol- 

 lowing year after the formation of the gall, the 

 perfect Fly, after passing through the usual 

 pupal stage, bursts forth from the interior, wliich 

 by this time has been reduced to an irregular 

 hollow filled with the larval excrement or 

 "frass," as it is technically termed. This fly 

 belongs neither to the genus (JVematits) which 

 has lour submarginal cells (Fig. 7, page IG), 

 nor to the genus (Prist iphoru) which has three 

 submarginal cells with the cell next the body 

 very long (Fig. 11, page 20), but to another 

 genus (Uuura) which has three submarginal 

 cells witli the cell next but one to the body very 

 long. But as we have dwelt at considerable 

 length upon this somewhat dry subject on jiagc 

 20 of this volume, we need not repeat here what 

 we have already said. Willi the exception of 

 this curious ditference in the structure of the 

 wing-veins, the figure of the Native Currant 

 Worm Fly, given on page 20, will represent 

 with sufficient accuracy the Willow-egg Sawfly 

 {Euura S. ovum, AValsh), except that the gen- 

 eral color of the latter is honey-yellow in the 

 female and greenish white in the male, instead 

 of black in both sexes, and except that the size 

 is ii little smaller and the body much less robust. 



The WiUoAV-biid (iall. ^ 



(Salicis gemma, Walsh). 

 For a long time, in the course of the winter 

 and early in the spring, we had noticed here and 

 there on particular twigs of the Humble Willow 

 {Salixhumilis) — a dwarf species which grows 

 on the driest uplands — particular bnds preter- 

 naturally enlarged in the manner show'n in 

 Figure 32 at h b, buds of the natural size being 

 represented at a a a. On cxaiiiining into such 

 enlarged buds, we found most of them reduced 

 to a mere hollow shell, witli a round pin-hole in 

 it, through which some larva must have made 

 its exit. A few such buds, however, which 

 had evidently not been depredated on by any 

 insect, instead of being filled by the normal 

 downy embryo leaves, contained a homogene- 

 ous grass-green fleshy matter. Here then was 

 a riddle to be solved ! What made these buds 

 swell so prodigiously? What converted the 

 organized downy' leaves into a mass of green 

 l)ulp .showing no signs of any organization? 

 What insect had disappeared through the pin- 

 hole, probably in order to transform under the 

 surface of the earth? For several years the 



