2 THE POPULAR SCIENCE MONTHLY. 



subsequently described the gall-inhabiting type of it, which I have 

 termed gallcecola^ in a rather insufficient manner,^ by the name of 

 Pemphigus vitifoUce. Dr. Fitch knew very little of the insect, as we 

 understand it to-day. It was subsequently treated of by several Ameri- 

 can authors, and in January, 1867, Dr. Henry Shimer, of Mount Carrol, 

 III, proposed for it a new family {Dciktylosphmridm)^ which has not 

 been accepted by homopterists, for the reason that it was founded on 

 characters of no family value. 



All these authors referred to the leaf-louse described by D.r. Fitch, 

 and never dreamed that the insect existed in another type on the 

 roots. During the few years following our civil war a serious dis- 

 ease of the Grape-vine began to attract attention in France, and soon 

 caused so much alarm that the Minister of Agriculture and Commerce 

 in that country offered a prize of 20,000 francs for an effectual and 

 practicable remedy ; and a special committee was appointed to draw 

 up a programme of conditions, and award the prize if it saw fit so to do. 



The disease is known as poiirridie^ or rotting, the roots becoming 

 swollen and bloated, and finally wasting away. There were no end of 

 surmises and theories as to its cause, until Prof. J. E. Planchon, of 

 Montpellier, in July, 1868, announced^ that it was due to the puncture 

 of a minute insect belonging to the plant-louse family [Aphididce)^ and 

 bearing a close resemblance to our gall-louse. The insect was subse- 

 quently described, by the same author, from the apterous form, under 

 the name of Hhizaphis vastatrix, and not till September of the same 

 year* when the winged insect was discovered, did he give it the name 

 by which it is now so well known. In January, 1869, Prof. J. O. 

 Westwood, of Oxford, England, announced^ the receipt of both the 

 gall and root-inhabiting types, from different parts of England and 

 Ireland, and his inability to distinguish between the two. In the same 

 article he announced having received the gall-making type from Ham- 

 mersmith in 1863, and having described it by the name of Peritymbia 

 vitisana^ in a notice communicated to the Ashmolean Society of Ox- 

 ford, in the spring of 1868, which communication was, I believe, never 

 published. In the spring of 1869," M. J. Lichtenstein, of Montpellier, 

 first hazarded the opinion that the Phylloxera, which was attracting 

 so much attention in Europe, was identical with the American insect 

 described by Dr. Fitch. This opinion gave an additional interest to 

 our insect, and I succeeded in 1870, while the Franco-Prussian war 

 was at its highest, and just before the investment of Paris, in estab- 

 lishing the identity of their gall-insect with ours, through correspond- 

 ence with, and specimens sent to. Dr. Y. Signoret, of that city. During 



' Report, vol. iii., § 117. 



5 Proceedings Academy of Natural Sciences, Philadelphia, January, 1867. 



3 Messager du Midi, July 22, 1868. 



^ " Comptes rendus de 1' Academic des Sciences de Paris," September 14, 1868. 



5 Gardeners' Chronicle, January 30, 1869. ^ " Insectologie Agricole," 1869, p. 189. 



