OF THE STATE ENTOMOLOGIST. 69 



MEANS OF CONTAGION FROM ONE VINE TO ANOTHER. 



The modes of spreading indicated last year have been fully proved 

 correct. There can be no doubt about the young lice traveling un- 

 der-ground along the roots of the vines, or in any cracks or minute 

 passages in the soil; while 1 had no dilliculty last August in finding 

 them crawling over the surface of the ground. Moreover, M. Faucon 

 and M. Gaston Bazille discovered not only the larvcTS, but the winged 

 individuals, passing abundantly over the surface of the earth last Sep- 

 tember, in France, and we thus have evidence that the winged insects 

 make good use of their legs. They have likewise been caught in 

 spiders' webs, and seen in other situations to which they must have 



louse was founil on wheat in several parts of France tlie past year, and that other root-lice, sup" 

 posed to be Phylloxera, were found by himself and others on the roots of several fruit trees. So 

 there is a well-known root-louse, producing knots on Apple, and others, either little known or ^mde- 

 scribed, on Purslane, Turnip, Persimmon, and many other plants in this country ; but they a^e dis- 

 tinct species, and the entomologist will want other proof than is yet forthcoming ere he can believe that 

 Phylloxera vas f at rixa,Uiniks anj-thing else but the Vine. CutM. Lalimangoes still further, and weakens 

 all faith in his deductions, by promulgating the abstract ideas that the soil is iniitreguated with plant- 

 lice, and that the increase of Phylloxera is in some way due to the destruction of birds. In support of 

 the view that the European insect is a distinct species, and was not introduced on American vines, he 

 makes three statements : 1st. He publishes the annexed letter from Mr. Borkmin, of Georgia, of 

 whom he obtained his American varieties, to prove that Phylloxera is unknown there : 



' ' In our region, the I'hylloxera is unknown. Riley observed it in 1SG4 in Missouri ; at that time 

 it was injurious to the Clinton; but in fact the plague which ravages our vines is known only to entt)- 

 mologists through sciemitic investigations; vintners do not dream of its presence, and the damage it 

 does is not worth speaking of." 



2d. That American vines arc not affected exactly alike here and in France, so far as his and my 

 experience go. 3d. 'Jhat he has distributed American varieties through divers countries where the 

 inalady is unknown, witliont introducing it. 



None of these statements prove his position. 1st. If the insect is unknown in Mr. Berkman's 

 section, (the State of Georgia is pretty large, but no postoflice address is given) , it only indicates that 

 it was not sent over on his vines, but does not prore that it was not sent from other sections, either to 

 France direct, or via England; while Mr, B.'s mere dixit that Phylloxera is unknown in his region, 

 without attending jiroof, will have little weight when we reflect that three years ago no one dreamt of 

 the existence of the root-louse in any part of this country. We have, moreover, seen that it does occur 

 as far south as Florida. 2d. The sort of argument that proves the insects of the two continents distinct, 

 because the vine? in the two hemispheres are not aflected alike, would equally pi-ove that the Oidium 

 Avhich so troubles grape-vines in Europe is not the same as ours; for there is good evidence that some 

 of our vines are sorely troubled with it here; whereas, he himself shows that his American varieties 

 are not aflected by it there. Yet I know of no mycologist who has studied the subject who doubts the 

 identity of the Oidium Tuckeri Berk, of Euroi>e and America. I have seen what was evidently the 

 same, prevalent in the vineyards of Michigan; but not to rest on 1113' own authority, I may say that Mr. 

 Husmann believes the two identical, and I shall append to this note the testimony of Mr. William 

 Saunders, of Washington. 



In considering the relative susceptibility of the same varieties in the two countries, defective, 

 imperfect experience and climatic and terrene influences are important factors which have been over- 

 looked by M. Laliraan. 3d. The statement that he has sent American varieties to dillerent countries 

 where the malady is unknown without introducing it, would have more force if he had stipulated the 

 varieties sent, and whether, when sent, he observed that their roots were lousy or not. 



Finally, the same author refers to my writings in a controversial spirit, and makes the same par- 

 donable mistake as have other writers, (see Dr. Le Baron, Prairie Farmer, September 21, 1872; A.H. 

 Trimoulet, M<-'m. sur la Miladic No\ir, de H Virjne, Bordeaux, 1873, and others), ot considering the ear- 

 lier conclusions, drawn from imjjerfect knowledge of the insect in America, without taking into 

 account the subsequent and more mature convictions of greater experience. He wonders how I could 

 recommend the destruction of the Clinton one year, and reverse the recommendation the year follow- 

 ing; whea a closer reading of my last year's article would very plainly give him the reason. As to 

 his criticisms of the classification adopted, I attach more importance to recognized American botanical 

 authority than to the opinions of one who even confounds the terms species and genus. M. Laliman 

 also publishes the contents of a letter of inquiry addressed to me, under date of December 1-i, 1871 



