THE AMERICAN ENTOMOLOGIST. 



ON THE PRESERVATION OP ENTOMOLOGICAL 

 CABINETS. 



i/ 



r.Y .JOHN L. LECONTE, 



[ From :l.e American Katuralisl fur Augusl. 1K(!I. ] 



I have tiiecl at various times many experi- 

 ments tbf the prcsevvation of eollections of in- 

 sects, but witli such limited success that 1 did 

 not tliinlc tlie results obtained worth publishijiii'. 

 For the sake of deterrin!>- others from inusninu 

 these difi'crent lines of unsuccessful atlcuiiils, ii 

 would be irscful, perhaps, to give a brief ac- 

 count of my failures before desiribing a pro- 

 cess recently devised, whiili seems to be both 

 simple and eflective. 



Corrosive sublimate and various preparations 

 of arsenic have been recommended by several 

 hi<i'h authorities. Tlic former, even when most 

 (lilutcd, will linally render the pin bridle by the 

 amalj^am developed: the latter, when used in a 

 very weak alcoholic solution so as to leave no 

 eftloresence on the specimens, will preserve 

 them well, but it is troublesome to apply, as the 

 insects must be thoroughly soaked with the 

 fluid before being placed in the cabinet. Binar- 

 seniate of potassa being deliquescent, sug- 

 gested itself to me as a material that might be 

 applied in greater strength, and nuxuy years ago 

 1 prepared two boxes of specimens with it. 

 They had a good appearance for some time, and 

 have niwer been attacked, but eventually a con- 

 siderable deposit or eflioroscencc came on the 

 surface, so that the specimens required cleaning 

 before they could be used for study. 



Painting the interior of the boxes with arsen- 

 ious acid was also only partially successful ; I 

 have seen, though not often, living larvae of 

 Tro(joderina in boxes thus prepared. 



Having thus failed in finding any satisfactory 

 mineral poison I then tried tlie vegetable 

 alkaloids. 



I soaked specimens in moderately strong al- 

 coholic solutions of strychnia and picrotoxia, 

 dried them, and put them into pill boxes with 

 Troyodenna larv;c. After some weeks the 

 specimens were partly eaten, and the larvae 

 transformed into perfect insects. 



The etlccts of benzine and carbolic acid are 

 powerful, but only temporary. The former is 

 preferable on account of its less disagreeable 

 odor, and may be used by pouring about a tea- 

 spoonful in each box; it must be renewed every 

 four or five months. 



Packing the collection in chests painted with 

 coal-tar has been also recommended, and would 

 certainly be efficient, but troublesome, and ren- 

 ders the collection, practically, nearly useless 

 for study, on account of the difficulty of access 

 to the boxes. Surgical art has, however, given 

 to us an iustruraent by which a poisonous liquid 

 can be rapidly and most cfleclivcly applied to 

 the entire surface of large numbers of specimens 

 as they stand in the cabinet boxes, without the 

 trouble of moving them. I refer iothaAlomincr. 

 Opinions may vary as to the nature of the liipiid 

 poison to be used, but after several trials I have 

 found the following formula to be quite satis- 

 factory; it produces no elllorescencc, even on 

 the most highly polished species, while the odor 



is quite strong, and persistent enough to destroy 

 any larvje or eggs that may be already in the 

 box : 



Saturated alcoholic solution of arsenious acid, 

 eight Huid ounces: Strychnine, twelve grains; 

 t'rysfallized carbolic acid, one drachm; Mineral 

 naphtha (or heavy benzine) and strong alcohol, 

 enough to make one quart. 



1 have not stated tlie (|uantity of naphtha, since 

 there are some varieties of light petroleum in 

 conimerce which dissolve in alcohol only to a 

 sliglit extent. These should not be used. The 

 ]ie:ivier oils which mix indetinitely with alcohol 

 are the proper ones, and for the two pints of 

 mixture ten to twelvelluid ounces of the naphtha 

 will be sufficient. 



Care should be taken to test the naphtha on a 

 piece of p.aper. If it leaves a greasy stain 

 which does not disappear after a few hours, it is 

 not suitable for this i)urposc. 



The best form of atomizer is the long, plated, 

 reversible tube; it should be worked with a 

 gum elastic pipe, having two bulbs to secure 

 uniformity in the current. The atomizing glass 

 tubes and the bottle which usually accompany 

 the apparatus are unnecessary: a common nar- 

 row-necked two ounce bottle will serve per- 

 fectly to hold the fluid. 



I trust that the use of the means here indicated 

 may render the preservation of insect collec- 

 tions less troublesome than heretofore, and thus 

 increase the interest of amateurs who fre- 

 quently become disgusted with the science 

 of entomology, by seeing the results of years 

 of active and intelligent labor destroyed by 

 a few months of inattention, or by careless- 

 ness in introducing infected specimens. 



KIM.IXt; APPLE-AVOiaiS HY MArillXKKY. 



The world certainly moves! Men are con- 

 stantly making discoveries, which though trivial 

 in themselves, greatly benefit their fellow-men. 

 The hay-band remedy against the Apple-worm 

 (Carpocapsa pomonclla, Linn.) is an e.xcellent 

 one, but we arc obliged to seek for the worms 

 which spin up under it, and crush each one 

 separately. Mr. D. N. Brown, an enterprising 

 fruit-grower of St. .loseph, Mich., has however 

 devised a plan of slaughtering them by whole- 

 sale, which commends it.-jelf to the good sense 

 of every a])ple-grower. Here it is, as given in 

 a late number of the St. Joseph Herald, by our 

 friend and correspondent, L. P. Haskell of that 

 place : 



••rUico early in .lunc n/./.-. iinl liav l]aii.:<. in tlic (iji-ks 

 of tlu! tree, 111- ti-iinli hi'lciv ihr InwVr linil.. an. I in tlies(> 

 the larvre will secrete tliini>c-l\ cs i,, .-nlir lln- .lirvsali^ 

 state. Onee in two \veel<s reniovi' llji-si. ra.^s, anil de- 

 strn\ 111.- in-c.ls. y\v Itrown does it very quickly and 

 cllV. ii\.n l,y |iav-in;,'ilie raff'i thi'iiuj,'!] a clothes-wringcr. 

 In ihi- ni inn.]- lie Ijclicvcs tlic imisaiice may be j,'ot rid 

 of; and > cl the rllni't will ho uscli's-^ unless eVei-y owner 

 of an on-hard docslhr same tlnii;;. Tliere nnisf \n-ui,ilrd 

 effort. J.ct evei-yinau feel it his dntvtn in--,- his nei^'ll- 

 hortoactat once and persistently, i-enieniherin- that, 

 •etenial yi;,'ilance is the price ui'—tjood fruit.''' 



