THE PRACTICAL ENTOMOLOGIST. 



101 



S. F., New Jersey. — The heads of wheat you send are 

 infested — not very budly, however — with the orange- 

 colored larvee of the common Wheat-midge, {Cecidomyia 

 Tritici,) an insect which was introduced into this country 

 Bome twenty or thirty years ago from Europe, and which, 

 according to re* urns from the different counties of the 

 State of New York, which were thoroughly sifted and 

 footed up by the Secretary of their State Agricultural So- 

 ciety, destroyed in one single year in that single State the 

 enormous amount of fifteen million dollars' -worth of 

 wheat. In England the largest amount of wheat it was 

 ever known to destroy in one single year was one-twen- 

 tieth of the entire crop. Such a small percentage as that, 

 American farmers would not think worth talking about; 

 but here the Wheat-midge often takes over half of the en- 

 tire crop. The reason is simple. In England there are 

 no less than three parasitic insects preying upon the 

 Wheat-midge; in this country there is not one, because 

 it wisely emigrated here without its parasites. One would 

 think that common sense would indicate to our Govern- 

 ment the good policy, as a matter of dollars and cents, of 

 importing the parasites, particularly as the whole opera- 

 tion need not cost more than a few thousand dollars. But 

 no. Although this plan was long ago recommended by 

 some of the best entomologists in the country, Dr. Fitch 

 for example, it has never been adopted, and probably 

 never will be. Why? Because our Legislatures think 

 that insects are such very minute objects, that they are 

 unworthy their notice; forgetting that the plague of flies, 

 the plague of lice and the plague of locusts were three of 

 the worst plagues that God in his wrath sent to af&ict the 

 rebellious land of Egypt. 



The Wheat-midge itself in its perfect or winged form 

 is a small two-winged Uy, shaped much like a musketo, 

 butcousiderably smaller, and with an orange-colored abdo- 

 men. It comes out in June from under the ground, where 

 it has lain all winter, the time varying a little according 

 to the latitude, and lays its eggs upon the ears of wheat 

 when they are in blossom. These quickly hatch out into 

 the orange-colored little maggots which do all the mis- 

 chief, sucking out the life-blood of the future kernel so 

 that it shrinks up to nothing. When full-fed they most- 

 ly go underground and construct a very filmy cocoon which 

 adheres strongly to the surrounding earth, and inside 

 which they transform next spring into the pupa state. 

 But a few remain in the ear and construct their cocoon 

 there, which fits so closely to their bodies, that it is only 

 visible where it projects a little at each end, the cocoon 

 itself being transparent and finer and more filmy than 

 the most delicate gold-beaters' skin. I found two such 

 specimens in the few ears you sent. European authors 

 long ago noticed these facts, as to a certain percentage of 

 the larvae remaining permanently in the ear, but strange- 

 ly enough thoy have been overlooked and misunderstood 

 both by Dr. Harris and by Dr. Fitch. The practical in- 

 ference to be drawn therefrom, is that when farmers are 

 ■ cleaning up wheat, which is infested or suspected of be- 

 ing infested by the Wheat-midge, they ought always to 

 burn up or otherwise destroy the " tailings." For these 

 "tailings" will doubtless contain many of the larvje that 

 have staid in the ear, which, if not destroyed, might hatch 

 out next season into the perfect fly and propagate the 

 breed. (See on this matter my Paper in the Proceedings^ 

 Ac, IV. pp. 5B3— 9.) 



As you say that your "Pedigree wheat," imported from 

 the Isle of Wight for seed, has for two years past been 

 badly infested by this insect, while the rest of your field, 

 which was sown with another kind of wheat, was unin- 

 jured by insects, I should recommend you to give up 

 growing "Pedigree wheat." Doubtless this variety is pe- 

 culiarly agreeable to the mother-fly, so that she gathers 

 upon it from all the other parts of the field to lay her 

 eggs thereon. Possibly, however, it might answer to grow 

 it by way of trap to concentrate all the Wheat-7nidges up- 

 on one spot; but of this you must be the best judge. 



M. H. Boye, Penna. — The ears of wheat and rye that 

 you send are infested by the larva of the common Wheat- 

 midge, which is often popularly called the Red Weevil. 

 You will find the information you want in the answer to 

 "R. F., New Jersey" in this number of the Practical 

 Entomologist. I found two specimens of the larvae in 

 your rye that had already made their cocoons, just as I 

 did in the wheat sent by R. F. This is a curious fact, be- 

 cause both Harris and Fitch ignored the possibility 

 of any larvae passing to the pupa state in the ear and 



coming out as winged flies the same season. Yet, from 

 these two examples, it seems to be comparatively a com- 

 mon thing. The same insect attacks indifferently both 

 wheat and rye. Farmers should always be careful to bum 

 their "tailings," when they clean up small grain known 

 or suspected to be attacked by the Wheat-midge; because 

 they will thus destroy many of the larvae that are now 

 proved to stay in the ear, instead of going under ground 

 as most of them do. I think it not at all improbable that 

 many of these larvae that stay in the ear will not come 

 out into the fly state till the following June, though the 

 fact is not noticed by English writers, who were well 

 aware that a certain percentage of the larvae staid in the 

 ear. I infer this from the analogy of other species of the 

 same genus. 



J. H. Foster, Jr., Penna. — The elongate-conical, brown 

 bodies about one-fourth inch long, growing from the leaf 

 of the Isabella grape-vine like so many thorns on a thorn- 

 bush, are galls made by some species of Cecidomyia or 

 Gall-gnat. I know two other kinds of galls made by gall- 

 gnats on the grape-vine, which are quite distinct from 

 these of yours. The larvae of all Gall-gnats are readily 

 distinguishable by what is technically called the "breast- 

 bone," which is a dark-colored homj process, generally 

 Y-shaped or clove-shaped, which is situated on the lower 

 part of the first joint behind the head, and the use of 

 which I believe to be to abrade the internal surface of 

 the gall so as to cause an unnatural flow of sap to the 

 part, upon which sap the larva lives. Most of these larvae 

 are blood-colored, orange-colored or yellow, with peculiar 

 bowel-like, curdy, white markings; but a few are entire- 

 ly pale semi-transparent whitish. The number of differ- 

 ent galls made by Gall-gnats on different plants is enor- 

 mous, but the perfect fly has been bred from but very 

 few of them, as they are peculiarly hard to rear to matu- 

 rity. For example. Baron Osten Sacken describes eight 

 different gall made by Gall-gnats on the leaves of different 

 kinds of Hickory, but he only bred the perfect fly from a 

 single one of the eight. 



Uarion Hobart, Illinois, — The oval bunch of eggs about 

 three-fourth inch long, surrounding a twig of the cherry 

 tree and shining with a certain glutinous substance which 

 protects them from the weather, is nothing but the eggs 

 of the common web-caterpillar of the Apple-tree, Clisio- 

 campa americana. This larva commonly feeds not only 

 on the apple-tree, but on cherries and plums both wild 

 and tame, and also on the birch, the willow, Ac, and on 

 all which trees the eggs are commonly found. It is re- 

 markable that these eggs should stand all the heat of 

 the summer's sun and all the cold of the winter's 

 winds, without losing their vitality. But there they 

 swing aloft, blown to and fro by every breeze, scorched 

 by the heat and parched by the cold, till the earliest 

 spring leaves put forth, when out of every egg that has 

 not been preyed upon by a minute parasitic Platygaster 

 issues forth a tiny worm, to gorge itself with leaves and 

 grow and grow, till it finally becomes a pale reddish 

 brown winged moth. There is another web-caterpillar — 

 Hi/phantria textor, Harris — which I find sometimes on the 

 apple tree and other trees, but much more commonly on 

 the Pignut Hickory — which produces a white, not a pale 

 reddish brown, moth. This, however, may be readily 

 distinguished from the other by its wanting the beauti- 

 ful sky-blue stripes and being much smaller and appear- 

 ing much later in the season. 



M. S. Hill, Ohio.— The clay-colored beetle nearly an 

 inch long and with six black spots on its back is Pelid- 

 nota punctata, a well known enemy to the foliage of the 

 grape-vine in its perfect state, though its larva to my 

 knowledge feeds on very rotten wood. The smaller beetle 

 not quite one-half inch long and varying in color from 

 almost entirely clay-yellow to almost entirely black is 

 Anomala lucicola, and' is likewise well known to attack 

 the leaves of the grape-vine. Its larva probably feeds 

 underground on the roots of plants. Both are figured in 

 Harris's book. 



The caterpillar you sent which infested the raspberry 

 bushes, "feeding with great voracity upon both the leaves 

 and the berries," spun its cocoon on the road, and I can 

 therefore say nothing about it. I hope to breed the per- 

 fect moth from it, when I will advise you further. The 

 insects were all well packed and reached me in first rate 

 order. 



