THE AMERICAN ENTOMOLOGIST. 



57 



ANSWERS TO CORRESPONDENTS. 



Tivigs amputated by sonic iiuKnoivii aui- 

 mal.— 6-Vo. Burnsije, South Pasn, /??.— It is a perfect 

 mystery to us what animal has girdled the, twigs which 

 you send, so that they break entirely oil" and fall to the 

 ground, or for what purpose it should operate in this 

 singular manner. We had heard a good deal from 

 various fruit-growers in the South about twigs being 

 amputated in this way, and had always hitherto sup- 

 posed it was done by some larva allied to the well- 

 known Oak-pruner, (ElapTiidioiiputator, Peck), which 

 cuts off the twig in which it resides Ulow the part W'hich 

 It inhabits, and thereby (alls eventually, twig and all, 

 to the ground, like the Irishman that sawed off close to 

 the trunk the Umb on which he was sitting. But your 

 twigs are evidently , as you remark, girdled from the 

 cvteide, and not cut oS inside the bark, which is the 

 manner in which the Oak-pruner operates. And be- 

 sides, one of the two twigs sent manifestly grew ahore 

 the point where the girdUng took place, and yet it con- 

 tains no larva and no borings, as it ought to do on the 

 Oak-pruner theory. In numerous apple-twigs, cut 

 off in the same manner as your specimens, which we 

 ourselves saw at South Pass, there is an egg every 

 here and there inserted under the bark in every 

 amputated portion. Hence it would seem that some 

 insect first deposits its egg in the twig and then 

 cuts it off. It would be very desirable to detect 

 the culprit in the act of girdling the twig, and if it 

 really is an insect, to forward it for our inspection . If 

 really an insect, it is not improbably some kind of 

 large beetle, and in that event wc can -only guess that 

 it amputates the twig, in order to afford a more suit- 

 able hatching place lor its eggs. Lut guessing is not 

 knowing, and faith is not science. Apple twigs, ap- 

 parently amputated upon the same principle as your 

 liickory twigs, were sent to us two years ago from the 

 State of Mississippi, by M. W. Philips. 



Twigs girdled by some animal. — Jiahje 

 Brown, Villa, Bidye, III.— The pear twigs you send, 

 which liave been amputated by some animal or other, 

 and most probably by some insect, are similar to the 

 liickory twig sent by Mr. Burnside and noticed in the 

 preceding answer. You say that you have noticed 

 much larger branches on the persimmon tree ampu- 

 tated in the same manner, and tliat you have supposed 

 that this was done by the opossum", in order to get at 

 the fruit, of which it is very fond, (in ahnosi, all 

 the specimens, of which wc have examined ,^ieal niiiii- 

 bers, whether on the pear, hickory, or per.sinunon, wc 

 find on the amputated portion o"ne or more whitish 

 eggs, about 0.10 inch long, of an oval shape, and about 

 oi times as long as wide, imbedded between the bark 

 and the wood. Usually tlicse cggsan^ insnlcd clusc lo 

 a bud, and on some specimens alnio.^t i\ii\ hinl lur :i 

 considerable length is thus funilslicd. i lii Uu' nilni' 

 liand, on the portion of the twig tlial remains uu the 

 tree, we find no such eggs. Ilencc we infer that, 

 whether the work be done on the persimmon, the hick- 

 ory, or the pear, it is in every case done bv some large 

 insect, and that the ciliicrt of that Imm-iI, in"amputaliii"- 

 the twig or bran. h iimlainiiii; its lu-s i, to keep tlicin 

 moist through the wiiilcr, hv rausiii^' the twiu' that 

 contains them to lie on thcgroiind \\ <cxii(rt liriialch 

 out some of the eggs iie.vtspring, whm wc shall he ahh- 

 to speak more positively as to the siachs lliat i)(ii;>niis 

 this extraordinary work. The cuns Ihrmschcs have 

 the character of those of certain Ca/i/d/,ls (genus Oiv/ie- 

 Umum), some of which we know to be deposited in the 

 iiutumn, by the mother insect, in the stems of woody 

 weeds. But the character of the amputation is rather 

 such as we should e.-cpcct from some largo, beetle. S 



Parl-er Earle, Hrjuth Pass, /K.— Your jicar twigs arc 

 amputated by the same insect as arc those sent bv Mr 

 Burnside, and by Judge Brown. 



Ilop-vinc Caterpillar—//. /. Panlap, Cham- 

 pm<jn, Ills.— The. worms which you send, and which 

 are eating the foliage of the hop-vines, arc the larvx of 

 the Semicolon buttertly. It is spoken of under the 

 head of "Insect foes of the Hop-vine," in answer to 

 Mrs. II. C, Freeman, in number 2 of this iournal, 

 page 3!). 



"Galls" ou leaves of Soft Maple. — />;■. A. 



L. Child, Glendale, Cass Co., i\«J)'.— The rouniUsh, 

 peduncled, wart-like, green excrescences, mostly on the 

 upper surface of the leaf of the soft maple, and the 

 largest of them only 0.15 inch long, are galls pro- 

 duced by a minute and almost microscopic species of 

 Mite , (Acarus family) . There is a much more elongate , 

 but otherwise very sunilar gall, that is commonly found 

 on the leaf of the sugar maple, and is generated by a dis- 

 tinct species of mite . To the former gall we have given 

 the manuscript name of Maple Pouch (Aceris loailus) ; L 

 to the latter that of Maple Purse (Aceris ciiimena). A 

 very similar one growing on the leaf of the Wild Plum I 

 has been illustrated and described by the senior editor 

 of this journal, in his First Annual Report (p. 43). 

 If you open your maple gall about the end of July or 

 the fore part of August, and examine it under a high 

 magnifying power, you will find in it scores of minute, 

 whitish, or pale-rosy youn» Mites, very dull and slug- 

 gish ill their movements when small, but always of an "^ 

 oblong-oval shape, and with thi-ee pairs of legs on the 

 fore part of their body, and one pair widely removed 

 from the others and placed on the hinA part of their hody. 

 It is by this characteristic arrangement of the hind pair 

 of legs, that the larva; of Mites— no matter whether 

 they have eight legs, or whether, as is sometimes tlie 

 case, they have only six legs— may be always distin- 

 guished at once from the larva; of Barklice and Plant- 

 lice; which otherwise often resemble them very closely. 

 All these leaf-galls originated by Mites, are foniied by 

 the mother Mite stationing herself early in the season 

 on one surface of the leaf, and gradually irritatin<'- 

 with her mouth the vegetable matter beneath her, until 

 it swells out and develops into a hollow gall on the 

 opposite side of the leaf, inside which gall the Mite 

 finds herself eventually enveloped, as if in a bag with 

 the bag's mouth loosely closed. She then, after laying 

 a_suflicient number of eggs, from which the young 

 mites subsequently to be found in the gall take their 

 origin, either wanders away through the half-open 

 mouth of the bag to found new galls, or perishes of old 

 age where she has laid her eggs. The rough and often 

 wooly scar, where these white galls have originated, 

 may always be plainly seen on the opposite side of the 

 Icat to that from which the gall itself projects. The 

 sulyect is a very curious one, but has hitherto been 

 illustrated by no other North American entomologists; 

 and but for the fact of our having ourselves paid par- 

 ticular attention to it, wc could not solve the enigma. 



ITiisightly g:alls on tlic Cottonwood— />r. A. 



L. Child, Glendale, ^Ye//.— The large scraggy coxcomb- 

 likc galls on your Cottonwood trees which have so in- 

 creased of late years, that the trees begin to languish 

 and die from tlieir inlluencc, and which remain on the 

 trees as unsightly bhu'k ohjcKs duriu-thc winter, may 

 he known as the -Na.ualH, ud -all, and Ihcv .are pro- 

 duced by a plant-lnusi; lichinuiim' to the -mils Pemphi- y 

 ■jiix, and which has hccn dcscrihed as rou/.hi.ius [hyrso- 

 ci-llpta] ca,jaJ„.,nhiK by the senior cilitor of this paper, 

 the imiicrfcctly .-lobular gall at the junction of the leaf 

 with Its stem, is the Poplar-stcni -all. It is caused by 

 a louse (Pemphigus pnpul!,-u,ilis. I'itcli), Ijclonging to (/ 

 the same genus, and of nun-h the same appearance as 

 the former. The best mode of ridding your trees of 

 these gaUs is to pluck and burn them upon their first 

 appearance in the summer. 



Insects named— .F. Jliufcr, Xavr.w,, /«.— What 

 you call a '• green cicada'' is the Slcndci- meadow Ka- 

 tydid ((hrh;ni„„m nr.jeile. liai-ris), an.l llic strange 

 snakc-hke animal which came out ot Us alMlomen is the 

 coniniou Horse-hair or Hair-snake ( Gurdius uquaticus) , 

 ihisllair-snake has not bin,- whatever to do with tiie 

 true Snakes, which arc liack-bone Animals ( feHch-ata), 

 but belong to the Intestinal Worms (Entozoa) which are 

 Kinged Animals (Artimlatu). It breeds within the 

 bodies of many other onrnopTEKOUs insects, and we 

 have often obtained it from different species of grass- 

 hoppers. The "new bug found on the grapevine" 

 IS the Indian Cetonia (Cttonia lada, Harris). It is 

 lound, at the present time of year, on a number of 

 plants, and is quite partial to sweet fruits. Dr. War- 

 der mentions it as being very destructive to the peach 

 m Ohio. 



