THE AMERICAN ENTOMOLOGIST. 



151 



middle of June, and ia southern latitudes in 

 the middle of May. From a large lot of galls 

 that had been found upon barley, obligingly 

 furnished to us by Mr. J. Pettit, of Grimsby, 

 Canada "West, the first flies came out June 9th, 

 and the)^ continued coming out in very large 

 numbers till June IGth and subsequently. As 

 is usual with most insects, the males came out 

 first, and not a single female appeared' until 

 June 11th; whereas from and after .Tune loth 

 there were nothing but females to be met with, 

 the whole number of females, however, greatly 

 exceeding that of the males. The cause of this 

 singular phenomenon of the males preceding 

 the females by several days — which has been 

 noticed by other writers in the case of other 

 insects, and which we believe to be a very 

 general law — has never been explained. But it 

 is probably due to the desire oti. nature, that the 

 males may have time to gain their full strength 

 and vigor, before the females csine into the 

 world and require their immediate attentions. 

 Be this question as it may, after coupling in the 

 usual manner, the female Joint-worm Fly 

 proceeds to lay her eggs in the stems of tlie 

 growing grain. The following excellent ac- 

 count of this operation, from the pen of Mr. 

 Pettit, we extract from the Canada Farmer for 

 18()7, page 268: 



About the 8th of June of the present year tlie 

 perfect Insects began to make theu' way out of the galls. 

 Si iS » is- s> lieing desirous of kuowiug more of their 

 liabits, I watched the growing barley, and on the 10th 

 of June found them actively at wo'i-k ovipositing in the 

 then healthy stalks of the plant. Before commencing 

 oporations'they walk leisurely up one side of the plant 

 as far as the last leaf, anil theu down the other, appa- 

 rently to make sure that it has not already been 

 oviposited in. Head downward, they then begin by 

 bending the abdomen downward, and "placing the tip of 

 the ovipositor on the straw at right angles with the 

 body, when the abdomen resumes its natural position, 

 and the ovipositor is gradually worked into the plant to 

 its full extent. With the aid of a good lens, and by 

 pulling up the plants on which they were at work 

 (which did not appear to disconcert them in the least), 

 I could view the whole operation, which, in some 

 cases, was accomplished in a few minutes, and in others 

 was the work of an hour or two. When a puncture 

 was completed , they usually backed up a little and 

 viewed it for a few seconds, and then apparently satis- 

 fied, moved to one side and comijicnced another. 



Very shortly after this time, the egg must 

 hatch out. For, upon July ."rd, we examined 

 a large lot of the green barley-galls, which had 

 been obligingly forwarded to us by Mr. Pettit, 

 and found the larva of the Joint-worm Fly 

 almost half-grown, that is from O.OOi to O.OOG 

 inch long, and about five times as long as wide. 

 In these green galls, upon the most careful 

 search, we could find no Gall-gnat larvas, nor 

 any vestiges of any such larv;e. So that we are 

 now fully persuaded, that the idea originally 

 entertained by Dr. Harris and Dr. Fitch, and 



subsequently favored by the Senior Editor of 

 this JouuNAL, namely, that these galls are in 

 reality made by some undiscovered Gall-gnat, 

 upon which the so-called Joint-worm Fly that 

 has been figured above is a parasite, is a false 

 and fallacious one. Otherwise, if the so-called 

 Joint-worm Fly were really a parasite, we must 

 certainly have discovered, at this early period 

 in the year, a few specimens of the larvoe upon 

 which it was parasitic, or at all events some 

 traces of their handiwork. Both Harris and 

 Fitch afterwards became of opinion, that the 

 Joint-worm Fly was the real author of these 

 galls; and we think it right to bear this public 

 testimony to the correctness of their entomo- 

 logical inferences. AVe write for truth, and not 

 for victory, and have never claimed to be 

 infallible.* 



By the beginning of September, the infested 

 grain having ripened long before this period, 

 the galls are alreadj^ dry and hard, and the lar- 

 v:e contained in them full grown, measuring 

 now about 0.13 inch in length. The great ma- 

 jority of these larvaj are destined to remain in 

 that state, enclosed in their little cells, until the 

 succeeding spring; but — as happens with many 

 different insects — a small percentage of them 

 seem to pass into the pupa, and thence into the 

 perfect state, the same summer that the eggs are 

 deposited. For, out of a lot of 124 barley-galls, 

 received September 10th from Mr. Pettit of 

 Upper Canada, 39 galls, or very nearly one- 

 third part, were already bored with the same 

 kind of small round holes as are made in the 

 succeeding sjjring by the escaping Joint-worm 

 Flies, some galls containing six such holes, but 

 most of them about three. It is true that we 

 are not personally cognizant of the fact, that 

 these holes are bored by the same Joint-worm 

 Fly, that escapes from similar holes in such 

 profuse abundance in the following June ; but 

 Prof. Cabell, of Virginia, stated to Dr. Harris 

 Avith reference to the wheat-inhabiting Joint- 

 worm, that he had known a few flics to leave 

 the straw the first year, but in each instance the 



•The Senior Eilitor of this JoiU'iial published in the Canada 

 Farmer for 1867, pp. 2*)7 — 8, a letter on the JJarley Joint- 

 worm, in which he disavowed and repudiated his former 

 skepticism (iis given to the world in the Practical Entomolo- 

 gist, I, pp. 10 — la, and 37—8), on the subject of this insect 

 Ijeing a true gall-maker. Dr. Packard, notbeingscieutitically 

 bound to rea<l all the Agricultural Periodicals that are 

 printed in America, has erroneously, and no doubt inadver- 

 tently, qnotedhim in November, 1KB8, in his Guide to the 

 Sludi/ 0} Insects, p. 30.t, as still retaining his original belief. 

 It is proper to add here that, in the letter in the Canada 

 Farmer, the same opinion on the classification of this insect 

 which will be subsequently elaborated in this article, M'as 

 brielly expressed as follows; ' ' The Joint- worm Fly differs 

 gi-nericaliy from all the numerous species of the Eurytoma 

 group, which 1 have ascertained to be parasitic on other in- 

 sects, and cannot, I think, be referred with any propriety 

 to the genus Eurytoma, althougli it undoubtedly belongs to 

 the Eurijtoma group . ' ' 



