116 



THE AMERICAN ENTOMOLOGIST. 



A POPULAR DELUSION. 



There are Iriljes of eiiliemeral iiisoets-wiiieli are Ijoru, 

 live merrily, grow old and die, witliiu the eompass ol' 

 tweiity-foiir hours. — AgrienHuntl Paper. 



Tliis is a vulg'ai' error. Tlierc is no known 

 insect that passes tlirough all the stages of its 

 existence, from the egg to the jierfect state, 

 in less than several -weeks. Tlic different spe- 

 cies of flesh-flies and blow-flies are familiar ex- 

 amples of sncl) a rapid development of life; and 

 we can readily see why it should be so with 

 creatures subsisting upon subslauces that decay 

 so cpiickly as carrion. Even with leaf-feeding- 

 larva?, it has been shown that the Colorado Po- 

 tato-bug arrives at the mature state in about a 

 month from the laying of the egg. But the 

 great majority of insects require iiearl}^ a year 

 to pass through all their stages ; several require 

 two or three years: and the Seventeen-year Lo- 

 cnst {Vic(tdu) actually re(iuires Ihc fall period 

 • of seventeen years to elapse before it becomes a 

 winged fly. 



There are, indeed, several flies known as 

 May-flies or Ephemera — one of which will be 

 found figured in onr first numljer (page C, Fig. 

 1 h) — that live but a very short time, and a few 

 of them only for ten or twelve hours, in tlie 

 winged state. But the larva? of these very same 

 flies have lived in the water for nearly a year, 

 before they left their native clement and became 

 denizens of the air. The proof of this fact, 

 which is notorious to all entomologists, can be 

 at once made manifest to every one. All these 

 May-flies drop tlieir eggs in the water shortly 

 after they have assumed the winged state : and 

 of none ot them is there more than a single 

 brood in a single year. Now if it were possible 

 for any of them ■' to be born, live merrily, grow 

 old. and die, within the compass of twenty-four 

 liours," as we are told above, then from these 

 eggs thus dropped in the water there would 

 surely spring up in a da\or two a second brood 

 of winged May-flies, and from these in the same 

 period of time there would be generated a third 

 brood, and so on indeflnitely all through the 

 summer, for at least a hundred successive gen- 

 erations. Wliereas the real truth of the matter 

 is, that there is but a single brood of each spe- 

 cies of May-fly in a single year, appearing in a 

 particular month, and not to be met with at any 

 other season of the year. For example, it is 

 recorded by European authors that a particular 

 kind {Ephemem Siimmmerdiana) swarms regu- 

 larly every year at the mouth of the Rhine, but 

 only during three successive days, which usually 

 occur about the feast of Olophius and St. John. 



It may perhaps be argued tliat, although tlic 



Avinged May-fly that flutters round in the air for 

 a few brief hours is developed from the body of 

 tlie larva that has been swimming about for 

 months in the w^ater, yet that the Maj'-fly is a 

 distinct animal from the larva. But no such 

 hypotlicsis is tenable. Every frog is developed 

 from a tadpole, or '■ pollywog," as it is popu- 

 larly called ; and the tadpole is as unlike the 

 frog in every respect as the larva of the May-fly 

 is unlike the May-lly itself. Shall we then ven- 

 ture to assert that the frog and the tadpole are 

 distinct animals? Or that calves, lambs and 

 colts, are distinct beings from cows, sheep and 

 horses? If so, then it will also follow that 

 babies do not belong to the same species as 

 growai men and women ; although in reality the 

 baby is as much the larva of the full grown hu- 

 man being, as the tadpole is of tlie frog, the calf 

 of the cow, tlic lamb of the sheep, and the colt 

 of the horse. 



Many years ago Dr. Franklin published an 

 address, full of very instructive philosophy, 

 which he put into the mouth of an '•' ancient 

 Ephemera," that liad lived to the extreme old 

 age of four hundred and Iw-enty minutes. As 

 with much of the popular literature of the day, 

 his moral reflections are admirable, but his 

 enlomologv is naught. 



THE SUUIRREL BOT. 



j;,i;/jj>'S AMen'ca,, Kntomo'lomst : 



In regard to the mutilation of the generative 

 organs of American squirrels, alluded to in the 

 January numberof your paper (p.8G), allowme 

 to make a i'cvi remarks. The emasculation of 

 the Gi'ay Squirrel {Sciurus caroUnensis) by our 

 common Ifed Squirrel (i5. hiuhonlus) has been 

 almost universally advocated by old hunters in 

 this region from my earliest boyhood. But they 

 always alleged that it was conflnedto the Grays, 

 and was perpetrated by the Bods. My intelli- 

 gent friend, Judge Libhart. of Marietta, Pa., 

 however, although he had shot emasculated 

 specimens of these, was not prepared to unite 

 with otiier hunters as to the cause. 



About flfteen years ago, I captured a large, 

 short, thick-bodied, two-winged fly, sitting on a 

 fence stake about half a mile from a wood. As 

 dipterous insects Avere not my specialty, this 

 individual remainedalong time in mycollection 

 unnamed. About seven years ago, ]Mr. Geo. 

 Hensel, a naturalist of this city, captured an 

 apparently sickly Striped Squirrel (Sciurux 

 striatus), which he brought home and confined 

 in a cage. For some time this animal refused to 

 partake of its usual food; indeed it did not seem 



