334 



THE AMERICAN 



Noctuadous anil Tovtriculous larvae to devour the green galls, 

 and sometimes from the trees on which I was experimenting 

 being afterwards mercilessly lopped of their main limbs, or 

 cut down to the ground, by their uuiirincipled proprietors 



On one occasion, being desirous of attaining some practical 

 proof that q. spongifica could generate q. actculata, as well 

 as the reverse, X strung a chaplet of some 50 or GO green Q. 

 sponr/ijica galls, gathered before it was quite time for C. q. 

 sjjongi/ica to come out of them, upon a i^articular bough of a 

 large isolated black oak, known not to bear these galls. 

 Luckily no mischievous person discovered this deposit, and 

 ill the course of the summer I removed it, so as to preclude 

 tlio ptj.ssiljility of any C. q. aciculaia coming out therefrom 

 and generating galls ujion this tree. The next spring I was 

 deliglited to see numbers of oak-apples upon the particular 

 bough on wliich I had strung the chaplet of oak-apples, and 

 np':in one or twoof the adjoining boughs, but none at all upon 

 the rest of the tree. Unfortunately, however, the caterpillars 

 destroyed most of lliem before they were fit to gather, and I 

 only harvested G galls , many of them in poor order. In 4 of 

 these the gall-maker was destroyed Ijy parasites, and the re- 

 maining 3 were barren ; so that all that this experiment proved 

 was tliat q. spongijlca was a gull-maker, and not, as Dr. 

 Iteinhard sug.gests may possibly be the case, an inquilinc. 



Upon anotlier occasion, wishing to repeat the very same 

 experiment as the last, I strung another such chaplet of green 

 oak-apples upon a large black oak, which I had noticed for 

 years to grow in a very retired spot upon the BluH's, with not 

 another oak of the same species within a quarter of a mile of 

 it, and which, as I was quite certain, had produced no Q, 

 s;)0H</i7>c(i galls for many years, if i I. had ever produced any 

 at all. Unfortunately for the interests of science, tlie German 

 citizens olliock Islaud determined about this time to have a 

 gi and lield-day in llie woods; and as ill luck would have it, 

 niall places in the world they must needs select my quiet re- 

 tired spot for tlieir Terpsiohorean exercises. The result may 

 be read ily guessed , Of course my cliaplet of oak-apples was 

 speedily discovered by some roving Teuton; of course the 

 conscript fatliers of the assembly held a solemn council as to 

 wliat miglit be the meaning of tliis dire and awful prodigy; 

 and of course it Avas unanimou-ily voted that the "spooks" 

 had placed tlie oak-apples tliere for the imrpose of souring 

 all the lager lioer, breaking the strings of all tlie fiddles, and 

 generally iuilicting all manner of horrible calamities upon 

 the festive crowd . Tlierefore the wizard spell must be broken , 

 and the "spooks" must be balked in their atrocious and 

 malignant imrpose. I do not know how the "spooks" felt 

 upon this occasion, but I know how I felt myself the next 

 morning, when I visited that venerable old oak and saw the 

 sliatteied fragments of my galls trampled into the dust be- 

 ueatli its umbrageous boughs ! 



I may say in one word— to resume the dignincd dullness of 

 a purely scientific memoir— that, so far as my experiments 

 proved any tiling at all, they all proved the same thing: 

 namely, that Cgnips q. aciculata gcnvvMy reproduces itself, 

 but often reproduces Cijnips q. spojigijica.; and consequently, 

 as I originally maintained, that it is a mere dimor]ilious Q 

 form of the latter. It may perhaps go on reproducing itself 

 for 13, 20 or even 50 years; but tliat every?, actculata will 

 eventually, in some year or other, generate q. spong-yi.a, I 

 have no more doubt than that the sun will rise on tlie morn- 

 ing of January 1st, A.D. 1900. 



In the Icpidopterons Psgclic helix, as I have been assured by 

 Dr. llageii, out of tliousands (if specimens bred within the 

 last ten years by l>rof aiebold,ull were females; but in 1807 

 the male \vas discovered to ocom-, tliough in very small num- 

 bers, by I'rof . Clauss. May it not be the case that Ilartig's 

 agamous Cgnij>s, and certain N. A. Cgnips which hitherto 

 have only occun-ed in the female sex— for exainiile, Cijnips q. 

 podagra, Walsh, of which I have bred in early spring about 

 two thousand females without a single male among them, 

 and have in vain attempted to procure a bisexual form in tlie 

 preceding autimm— may, sooner or later, perhaps not till | 



after the expiration of many, many years, produce a genera- 

 tion of males ? In the Cynipidous genus Rkodites the males 

 are for the most part extremely rare. In certain species of the 

 Pseudoneuropterous genus Psocus—Ps. bipunclatus (Europe) 

 and Ps . varicgatus (Km-ope) — "you may," in the words of 

 Dr. Ilagen, " tind thousands of females together and not a 

 single male." {Proc. Ent. Soc. Phil. 11, p. 168.) Many 

 other such cases have been recorded by entomologists, as 

 regards insects belonging to many different Orders . And 

 from such a state of things it is but a single step to the non- 

 productiou of males for one, two or more years. The rarity 

 of males, however excessive it may be, even if it amounted 

 to but a single male to a billion of females, is merely a ques- 

 tion of mode and degree. But the permanent non-existence 

 of males in any species belonging to a Class which, like that 

 of Insects, is almost universally bisexual, would be such a 

 violation of the analogies cf Nature as I am loath to believe 

 in. 



To return from this long, and I fear somewhat tedious, 

 digression: No man can distinguish between the imago cf s 

 ot Halesidola tcsseltaris, Sm. &Abb. , the larvaof which feeds . 

 iqion a great variety of trees, but never on the Sycamore 7^ 

 (Plalanus) and that of H. Harrisii, Walsh, r lie hirva of which 

 feeds exclusively on the Sycamore, and dies if transferred 

 to trees upon which the other larva flourishes ; and yet these 

 two larvai are invariably as different from each other as light 

 is from darkness.* Many more such cases might be quoted, 

 but one such is enough to prove the importance of attending 

 to the larval history of insects. 



Dr. Fitch long ago asserted that the common imported 

 Apple-tree Bark-louse {Aspidioim conchiformis, Gmelin) 

 occurred also upon a N. A. dogwood {Cornus sericea); and 

 he sent specimens ofbotii insects to the English entomologist, 

 ,Iolin Curtis, wlio likewise pronoimced them identical. (JV. F. 

 Rep. I, p. 34) I liave recently been assured by Dr. Hoy, ot 

 Racine, Wisconsin, that to his knowledge this same bark- 

 louse lias existed in the neighborhood of Racine upon the 

 same species of dogwood for the last twenty years and up- 

 warils, and that " there is not the least shadow of a doubt 

 that the Dogwood was affected by this bark-louse long before 

 any white man settled in Wisconsin." Now, it is only 

 within the last few years that the imported Apple-tree Bark- 

 louse has worked its way into Wisconsin from tlie Eastern 

 States: consequently, the Ijark-louse that inhabits the dog- 

 wood can scarcely be capable of living upon the apiile-tree, 

 for if it had been so capable it would surely have attacked 

 the Wisconsin apple-trees long ago; whence it follows that 

 the two forms must in all probability be essentially distinct 

 in their digestive organization, and consequently that they 

 are distinct species. And yet, on the comparison of cabinet 

 .specimens of each, the apple- inhabiting foi-m and tlie dog- 

 wood-inhabiting Ibrm w^ere iironounced to be tlie same 

 identical species b}^ no less an authority tlian John Curtis ! 

 The real truth of the matter I believe to be, that in no one 

 single case can the same species, either of Bark-louse {Coc- 

 cidcD) or of I'lant-louse {Aphida) , e.Kist upon two species of 

 plants whicli, like the Apple and the Dogwood, belong to 

 distinct botanical families; although, on tlic other liand, 

 many other families of ii>sects are notoriously polyiihagous. 



Wlnit candid entomologist, who has worked much upon 

 any particular Order, will not :illow that there are certain 

 genera wliere it is ()I'ten almost or quite impossible to dis- 

 tinguish sjiecies by tile mere comparison of cabinet speci- 

 mens of tlie iiiKign.; Liew and Osleii .Sacken have said this 

 of the genus Ccciduingia in Diptera; Osten Sackeli of two 

 otiier Dipterous genera, Scia-ra and Ceralopogoii; Norton of 

 the genus Nematus in Hymeiioplcra; and Dr. LeConle lately 

 assured me that, although wlu-u he was a young man be 

 tliouglit himself able to discriminate, in the closet, between 

 lllr ililVereiil specie,j of Brachiniis in Coleoptera, he now con- 

 sidered it quite impracticable to do so with any degree of 

 certainty. And yet who doubts the fact of the existence, in 



* 5i;c my iiapcrs on Phy tophilgic Specie s already referred to . 



