25 



numbers of green, fleshy excrescences, about the size of a small pea. 

 I was the first to observe, in the columns of the Practical Entomolo- 

 gist, that it does not attack indiscriminately all our native and culti- 

 vated grapevines, but is peculiar to the Frost Grape {Vitis cordifolia) 

 and to a small number of our cultivated varieties, namely, the Clinton, 

 the Delaware, and, according to Mr. George Husmann, of Missouri, 

 the Taylor. Dr. Morse, of Missouri, who has had great experience 

 with the grape, confirms the truth of the above assertion, and inform.^ 

 me that in Missouri the Delawares are sometimes covered with these 

 galls so as to injure them greatly, and that he has occasionally seen a 

 few of these galls even on the lona vine, which, according to Mr. Wil- 

 liam Saunders, is a variety of the Northern Fox Grape {Vitis lahrus- 

 ca.) One of my correspondents has informed me that a whole vineyard 

 of Clintons near Bloomington, in Central Illinois, was destroyed by 

 this insect in 186G; and it is undoubtedly this variety of the cultivated 

 grape that is the most subject of any to i-ts attacks. Even at such a 

 remote point as Clinton County, in the Northwest corner of Missouri, 

 the Clintons are reported as "not doing well" on account of their 

 leaves being covered with these galls. {Agricultural Report Missouri, 

 Appendix, p. 135 — 6.) What is very remarkable, and well illustrates 

 how certain species of insects swarm periodically and then are not 



louse [Coccus) Family, rather than to the Plant-louse [Aphis) Family, I long 

 ago explained. (See Pract. Entoni. II., p. 19, and Proc. Ent. Soc. Phil. VI., 

 pp. 283—4, notes.) 



To this new genus of his. Dr. Shinier refers, not only the insect which 

 forms the subject of this chapter, but also a mythical and entirely imaginary 

 species — Dact. glohosa, Shinier — which he has concocted by taking the wing- 

 less individuals of the Bark-louse of a very small Hickory-gall [Caryce semen, 

 Walsh MS., Proc. Ent. 8oc. Phil., VI., p. 283,) and the winged individuals 

 of the Plant-louse of a much larger and very distinct Hickory-gall [Garyce- 

 glohuli, Walsh, ibid. I., p. 309,) and assuming, loithout a particle of proof, 

 that the latter are the winged males of the species to which the wingless 

 females of the former appertain. And yet, even according to his own ac- 

 count, (p. 2,) the galls containing these so-called males are ''0.25 inch, and 

 even more, in diameter," while the galls containing the wingless females are 

 according to him, only "0.09 — 0.14 inch" in diameter, and, in reality, are still 

 smaller than he represents them to be^ ranging from 0.06 to 0.10 inch in 

 diameter; and, moreover, as will be shown below, the two galls differ by a 

 very remarkable structural character. It is -a very 'suggestive fact, too, that 

 the large galls, containing the so-called males, occur abundantly and com- 

 monly on the Shellbark Hickory and but in small numbers and rarely on the 

 Pignut Hickory; while the galls containing the so-called females of what 

 is supposed to be the, same species occur exclusively on the Pignut Hickory, 

 and in the most exuberant profusion. Whereas, if these two galls apper- 

 tained to the same species of insect, on whatever species of Hickory one of 



