THE CA.NADIAN ENTOMOLOGIST. 199 



" Grceca obscura, as Linnaeus puts it." The foreign authors referred to 

 have evidently fallen into error in this matter. 



Let us now see what we have before us concerning the Psylla. Mr. 

 Fletcher, in his interesting paper on the Homoptera, in the Society's last 

 report, gives us Prof Riley's notice of the Flea-lice of the Nettle-tree " in 

 full." That notice is a mere allusion, a reference to a gall, not a proper 

 description of the insect, as Prof. Riley assures us. The Professor tells 

 us also that P. vennsta has not been properly described. Osten Sacken's 

 account, supplied to me by a friend, is this : " I raised out of the gall a 

 beautiful large Psylla — Fs. venusta n. sp. — with the wings variated with 

 black. The peculiar shape of the apex of the metasternum and the 

 venation of the wings will, perhaps, necessitate to make a new genus for 

 this species." Mr. Fletcher has shown that the tree, Celtis occidentalis, is 

 rare in Lower Canada. When, then, I met with this rare tree, and found 

 the undescribed Psylla upon it, I felt justified in sending a description of 

 the insect to the Entomologist. But, really, the tone of Prof. Riley's 

 remarks gives rise, within me, to an uneasy feeling that, somehow, I have 

 been trespassing on the Professor's private preserve of Pachypsyllids. I 

 can only offer as my excuse that, as Entomologists, we want information. 

 What information have we concerning the Psylla we are considering, 

 apart from my own description, and Mr. Fletcher's admirable account 

 published subsequently ? What, beside the illustrations, has Prof. Riley 

 added to our stock ? He tells us that he called an insect, already named 

 P. venusta, '■'■P. celtidis-gratidis" ; that this insect is very large (Osten 

 Sacken had told us it was large) ; that there are differences, as regards 

 position and size, between the gall it produces and that produced by P^ 

 celtidis-inamina; that P. celtidis-mainma so closely resembles another 

 species, however, that " without the galls, it would be difficult, if not 

 impossible, to separate them — a not uncommon occurrence among gall- 

 producing species." 



Now, an accidental puncture, by the mother Psylla, of the leaf-stalk, 

 through which the nourishment of the leaf flows, would naturally produce 

 a larger excrescence than a puncture of a vein ; and a larger supply of 

 food would as naturally produce a larger insect. We know, to our-sorrow 

 and perplexity, that the rage for re-classification, and for raising varieties 

 into species, is becoming a vice on this side the Atlantic. And we really 

 have nothing before us to show that the P. venusta of Osten Sacken, and 



