ENTOMOLOGIST AND BOTANIST. 



331 



A>, to llK liyi otIicM!, bio iLhtU liy I)i Beiiilmid • tli it Hit 

 lorm q anculata is the onlj tiuegill m ikiDfe toim iiii I tli it 

 botl / sponnfi a iu\\q i«a;Marc iii i iliii«i-> that i', iiit 

 del iitly uliit*. 1 b\ th 11 I 1 tl I 1 I 



; V tc 

 dimorph. s <, to c 

 tticse tw. forms i I 

 doiibtflil lit to 

 piorliice 1 1 CSC t o for 

 ture and j sent a n 



are, 



loljtl 



fact 1 



other. II s V ry t e th t tl e 

 galls, of cr mi 1 st ct c 



tiiiguished from one another, although they are the work of 

 distinct gall-makors. Indeed, polythalamous galls are very 

 generally more difficult to characterize than monothalamoiis 

 gajls, because their shape and tize depend upon the number 

 of gall-making larva; that they contain, which will often 

 vary from two or three to two or thi-ee score . Monothalamoiis 

 galls, on the contrary, are as definitily limited in size and 

 shape as are the great'majority of tti^ In!! ii n; .pi i iis of in- 

 sects; and moreover, as a rule, ii; ii .h more 



numerous and more accurately diin, (.,. ri,.ii ,, i, is than 

 do polyllnilanioils gulls. Now, llir.ii ill ihai \\ii;irellow 

 conririii il w nil -I Ikii 111 ' v'"/ ' ■'■' ■ ' — i^ a monothala- 

 moiis .1 ill I i' ■ III ■ I 'ili/ed, and just .as 



easily 1 1 i ■ aii . 1, i 1 1 i i ■ . i i" h, nr a plum; and, 

 moreu\n-, ihu n.ill^ .lull |,niilui;i. Uiu .luLunuial dimorphousf 

 form ((/. acUuliita) occur upon the very same tree, and in 

 company with those that produce the vernal bisexual form 

 (<7. spongijica ^Q). 



Dr. Weiiiliard, in the paper already referred to (p 7), in 

 ronliiiiiatiou of his second hypothesis of C. q. spongijica and 

 C q iiiiiulata being each of them true gall-makers, produc- 

 ini; ii|)<>M ihc same plant galls that are apparently, but not 

 really, identical, quotes the following two European cases 

 of iinilistinguishable galls being produced upon the same 

 plant by distinct insects: 1st. Two exactly similar twig-galls 

 on blackberry, produced respectively by Limoplera rubi and 

 Diustrophus rubi. Now, 1 am familiar with an undescribed 

 N. A twig-gall, Rubt nodus, Walsh MS., produced by an 

 undescribed Lasioptera allied to L. soHdaginis, O S., upon 

 an American blackbcny. This blackberi-y-gall is a simiile 

 enlargement of the twig, usually but not always on Hie part 



* Berlin Snumtol. ZeUtclir,lX, p. 9. 



1 loducid on tliesi 

 pi lilt and 1 y the \ 

 Ctci lomj 1 Ion's bl' 

 may leisonibH I 

 ituie In that! 

 I-, being » uc 1 



I-, alao I ol> thalanioua , and as it i!> 

 geuub fiUnta on thesime pait of the 

 s ime C 1 1 lomyi lous subginus as the 

 111 111 I km ol by ULinhai 1 it 

 II lis list IS of B similai 

 that! I I \ 1 J astonishing in 



uc 1 I I asimilai „ ill ma Ic 



I lit 1 tl |1 I I Dtashophus nl 



tis luofcl I J 1)1 H 1 II lis tint 1 Iw nil 

 ible It If gills u| on que cus ecu is pioUitil 

 I ^ Ce dnv /m < r ?! ! « ( 1 I I l 1 t ;n 7 ■! 



I c leatw „ 11 1 uo„w 1101 'HI J 

 n I c b 1 Lo. opte a all c 1 to L «o/ rfaj n s O S b t 

 1 st n t fron the si c eb j st v f r 1 1 as b d f on a 

 111 kb y „ 11 I b i J i d two SI c m cf of 



jnerg s botl ^e % Ce op re 1 I Ijne gus 1 e ^ Cy 1 

 1 I oto o sly q 1 o the h b ts M J 



il 1 



J dge f 1 

 ) I 1 



(del 



those facts are the logical results from the premises . I shall 

 not be surprised, however, if, in spite of all that I can say, 

 my theoi-y is received with as great incredulity as that with 

 which I formerly received the important discovery of Wag- 

 ner, in regard to the viviparous reproduction of the birvic of 

 a certain genus of Cecidomyidce. 



On October 29th and November 6th, 1864, I colonized a 

 number of these agamous g.all-llies, that Iliad bred myself 

 from oak-apples, upon throe different isolated black oaks, 

 that I knew to have not been previously infested by these 

 galls for many years back Two of these Ivoif. \vi rii very 

 large— say about 2J feet in diaiiii i< ml lin I nil ml I |il;ic,ed 



the gall-flies upon one partinii 1 inch 



of them, and on no other pan I I I Mi h luas 



small — say 1 foot in diametL-v :i I im Imm- n.l I pi.'. nl the 

 gall-flies on the trunk of this tree, ;ii tin- iiniiit when- the 

 main branches took their origin . 



On May 21, 1865, I examined all these throe trees. The first 

 large tree had no galls at all on it. The second large tree 

 had produced four Q. spongijica galls, partly on th<> very 

 bough on which I had placed the gall-flies in the priceding 

 autiunn, and partly on some boughs that immediately ad- 

 joined it. I estimated that the portion of this last tree thus 

 occupied by galls did not form more than ene-twentieth of 



the whole tree; so that, even if we sup 

 wandering Cgnips q. anculata had flov 

 the neighboring woods in the precedi 

 insect, coming out as it does so late 11 

 luctantly and as dully as a Plant!" 

 about la to 1 that they would not have n 

 portion of it found to bear galls in the 1 



♦ Sec Proc. Ei\t. Sac. Phil. IV, pp. 331 and 33lj. 



that < 



