ON A LECANIUM FROM ROCHESTER, N.Y. 335 



rently j9(?rsic(tf. While the possibihty exists tho^t juglandis and 

 Ijerskce are but forms of one species, I think that with present 

 information we must hold them distinct. In the Rochester 

 jiKjIandis I found the anteunte but seven-jointed ; whereas 

 Signoret gives persicce as having eight joints. Otherwise the 

 anteun?e of the two forms are very much alike. 



It may be added here, that the antennae of Y\.iQh.''& jiiglandifex 

 are likewise seven- jointed, a circumstance which favours the 

 belief that juglandifex and the Eochester juglandis are the same. 

 This was not stated in Fitch's description, and could not be 

 ascertained from Fitch's type, but appears in specimens found on 

 butternut in New York State, sent by Mr. Slingerland. Mr. Joseph 

 F. Bennett, one of my students, made a careful examination of 

 these specimens, and has drawn up a description. The antennae 

 are as described above for juglandis in all essential particulars, 

 but the fourth joint is possibly not quite so long, so that 

 Mr. Bennett writes the formula 3 (47 1 21 (56). The formula also 

 sbows '2i somewhat longer than 1, but this results from the position 

 of the segments, as may be seen from the drawing accompanying 

 the description. Practically, one may say that the antennae of 

 the butternut form {juglandifex) and of the Eochester juglandis 

 are identical in character. 



Another difficulty of quite a different kind has arisen. Mr. 

 Slingerland has very kindly sent me a copy of a paper, by 

 Eudolph Goethe, which I had not seen. In this paper (in 

 Jahrbiicher d. Nass. V. f. N., 37) the author describes several 

 species of Leucanium, including one found on Juglans, which he 

 considers to be L. juglandis, Bouche. Mr. Slingerland observes 

 that neither the description nor the figure tallies with the 

 Eochester species, and in this I can entirely agree with him. 

 Goethe's juglandis is a large species, shaped almost like a 

 Kermes, and appears to be allied to L. tilice, L. cesculi, &c. 

 Whether it is a known species on a new food-plant, or a new 

 species altogether, the description scarcely permits one to decide ; 

 but that it is true juglandis of Bouche I cannot bring myself to 

 believe. I do not suppose that Bouche 's types are still in 

 existence, and, failing these, we must necessarily demand that 

 a species identified as juglandis shall agree with his description, 

 which Goethe's scale by no means does. 



Goethe goes on to describe L, persicce, but differentiates from 

 it, a few pages further on, a supposed new species, which he calls 

 L. variegatum. This species, found on plum, is, to judge from 

 the particulars given and a characteristic figure, none other than 

 our Tiochesiev juglandis ! Thus we have evidence that this scale, 

 newly found on plum in America, has infested it for at least ten 

 years in Central Europe, Goethe's paper dating from 1884. 



To finally sum up, I have to say that it still appears to me 

 that the Eochester scale is Leucanium juglandis, Bouch6, of 



