THE PRACTICAL ENTOMOLOGIST. 



85 



insects are very capricious — the Bag-worms may prefer 

 late Apple-trees fi:>r some unexplained reason. In the 

 same manner certain varieties of Plum are peculiarly 

 subiect to the attacks of the Curculio, and the Peach-blow 

 variety of Potato is avoided, when possible, by the Colo- 

 rado Potato-bug. 



To restore your late Apple-trees to a healthy bearing 

 state, all you have to do is to pluck off and destroy, care- 

 fully and effectually, for one single winter, all these egg- 

 bearing cocoons that you can find on them. You will 

 then put a permanent check to the future propagation of 

 the insect ; for the females have no power to fly in upon 

 your trees from other quarters, and the chances are 

 greatly against one of the larvae reaching them for many 

 a long year to come. Mr. Glover as well as yourself — as 

 you will see from the passage which I have quoted from 

 him — has noticed these Bag-worms to occasionally infest 

 the Cotton-plant. 



F. T. Pember, TJ. Y. — The centipede which you now 

 send (No. I) belongs to an entirely different group from 

 Poli/desmus and lulus, having only a single'pair of legs to 

 each joint of its bo'ly instead of two pairs. ' This group is 

 supposed by Dr. Wood to be carnivorous. No. U is the 

 larva of some small beetle, somewhere in the neiglibor- 

 hood of the Nitidula familv. Nos. 3, 4 and 5 are young 

 individuals of the Pretty "Poroellio (P. limatus) of Fitch, 

 one of several species described by that author, and com- 

 monly known as "Sow-bugs." They are not insects, but 

 Crustaceans. There is probably some mistake about the 

 Oniscus asellus of De Kay's Nat. History of New York. 

 Dr. Fitch says that the genus Oniscus does not occur in 

 New York, and asellus is a European species. The 

 "cocoons" found among the turnip roots are the coarctate 

 pupse (puparia) of some species behmging to the great 

 M'usca family, which is now subdivided into many dis- 

 tinct families. They resemble one another too closely 

 to refer them to any particular genus or species. I will 

 give the information you desire about entomological ap- 

 paratus in a future article. 



StoTTs, Hsirrison & Co., Ohio. — The eggs sent are those 

 of a Catydid, and the same as those referred to in the 

 answers to C. M. B.. of N. J., and Geo. Haines, of N. J., in 

 P. E. II. pp. 57 and 73. 



Jo3. Wood, Ohio. — When I said that " if any insect 

 punctured grapes as the common Curculio punctures 

 Plums, it was an entirely new fact," I meant that no 

 such fact was on record. You think that you have ob- 

 served such a fact, and say that you have " every year 

 hundreds of thousands of grapes punctured by some in- 

 sect, and afterwards find the larva eating the grape. The 

 grape does not rot, but'after a while drops from the stem 

 before it becomes ripe enough to cut. sometimes showing 

 a premature reddening. Mr. Moran's grapes, no doubt, 

 had the black rot and nothing else." (See P. E. II. p. 

 56.) I shall be glad to receive the promised specimens 

 next-summer. The facts you mention certainly seem to 

 show that you are right ; but I can tell better what to 

 think when I see what kind of larvEe are in the diseased 

 grapes. Several larvje producing two-winged flies are 

 already known to breed in decayed grapes, just as they 

 breed also in other kinds of decaying vegetable matter. 



H. C. Monger, Virginia. — Your suggestions shall be at- 

 tended to at as early a date as possible; but we are often 

 cramped for room in our little Journal. 



J. N. MoLBod,.Wisc. — Most of the cheap microscopes 

 are good for nothing. As to the one advertised in the P. 

 E., I am not acquainted with it. A really good micro- 

 Bcope of very high magnifying powers costs a large sum 

 of money ; and for all ordinary purposes you will find 

 simple lenses, either Stanhope or Coddington, such as 

 you can procure of Jas. W. Queen A Co., of Philadelphia, 

 amply sufficient and much more convenient. 



John B. Lyon, Ohio. — The cocoon sent was mani- 

 festly the work of some large Moth, perhaps of Attacus 

 Prometheus. Inside it I counted no less than 19 smaller 

 cocoons, closely agglutinated together in an oval mass, 

 and each containing a larva. These larvae had lived in- 

 side the body of the larva of the moth, devouring its 

 vitals till they finally destroyed it after it had spun its 

 cocoon, but before it had passed into the pupal state; 

 for there was no pupal shell in the large enveloping 

 cocoon. The 19 larvas, if undisturbed, would have de- 

 veloped this coming summer into some kindof JcAneitmon- 



fly, but what particular species I cannot say. I should 

 have liked to breed the JcAncMwion-fly from tliem,as Ihey 

 were entirely new to me, but, owing to not having been 

 enclosed in a little pasteboard box, they reached mo 

 pressed as flat as a pancake, and ruined except as speci- 

 mens for examination. Larvae require as delicate hand- 

 ling as young babies; and i presume that in Ohio, when 

 you want to send a baby any distance, you do not usually 

 enclose it in a simple post-office envelop, and entrust it 

 to the tender mercies of Uncle Sam's mail-bags. 



Dr. Benj. Norrls, Illinois. — The larvre s])lit out of 

 Hickory wood are not Buprestidous but Cerambycidous, 

 and no doubt belong to the pupie which you send with 

 them, and which were found in the same stick. If these 

 last, as you suppose, belong to Cli/tus pieius, then the 

 mature larvje of that insect has got legs, and Dr. Horn 

 must have been mistaken in supposing it to be legless. 

 (See Proc.&c. V. pp. 204—5.) I suspect that the larva of 

 both piclus and robinice are legless when immature, and 

 afterwards acquire short legs. At all events, younglarvEO 

 sent me from Kansas as those of the Locust-borer, were 

 legless. The larvae enclosed in cocoons are those of some 

 Fossorial Wasp, many of which make their nests in the 

 old deserted holes of Borers. 



W. W. Linn, Illinois. — The eggs on your apple-tree 

 twigs are those of the common Plant-louse of the Apple- 

 tree, respecting which see my Article on Plant-lice in the 

 P. E. II. p. 39. They may be found at this time of the 

 year on almost all apple-trees in larger or smaller num- 

 bers. You need not alarm yourself about thein, as these 

 Plant-lice, almost as soon as they hatch out, will be at- 

 tacked by myriads of Insect Foes, as I have explained ia 

 the Article already referred to. 



Isaac Hicks, N. Y.— The Bark-louse of the Tulip-tree 

 which you send is the most gigantic species I have seen 

 in this country, and is hitherto undescribed. The speci- 

 men had been bored above by some parasitic insect, and 

 from some of the others there jolted out on the road the 

 pupa-cases of a parasitic two-winged fly belonging ap- 

 parently to the genus Leucopis, which is known to infest 

 b;trk-lice. I sliall be glad of full-grown living specimens. 

 What you take for ** suspicious looking eggs" on the bark 

 are the young bark-lice already hatched out. 



The cocoon of the " Basket- worm" is exactly like one 

 which I have just received from Georgia. This insect, as 

 is perpetually hapjjening, has been differently named by 

 different authors, each ignorant that the preceding au- 

 thor or authors had already named it. In such cases the 

 scientific etiquette is, that the first name which is accom- 

 panied by a good and sufficient description, takes prece- 

 dence of all the others. Consequently, as has been shown 

 by Dr. Clemens, Thyridoipteryx ephemeraformis is the 

 correct name of this insect. Your remark that " in one 

 locality on Long Island, N. Y.. they were very plenty 

 and destructive to the evergreen only," is interesting, as 

 it confirms the fact that they prefer evergreens to decidu- 

 ous trees. I cannot identify the "vine- hopper" without 

 specimens. 



R. B. Palmer, Mo., per Edt. Rural World.— Iha apple- 

 twig sent is infested with the terrible imported Bank- 

 louse, not the native species which is comparatively 

 harmless. See on this subject. Practical Entcmologist 

 II. pp. 31 — 2, where figures of both are given, so that he 

 that runs may tell the difference between them ; and see 

 also the answer to Dr. Houghton in this number. 



^^"Answer to C. F. A., N. J., will be given in the next 

 number. 



irOTICE. 

 The American Naturalist is published in magazine 

 form by the officers of the Essex Institute, Salem, Mass., 

 at the usual price of $3 per annum. It is devoted to the 

 popular exposition of all departments of Natural History, 

 and the first number, which makes its appearance this 

 month, contains several valuable articles. We notice 

 particularly the first instalment of an interesting paper 

 on the American Silkworm, [Aitacus polyphemus), by Mr. 

 Trouvelot. 



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