ROEBUCK : ON YORKSHIRE CYNIPID^, 33 



to prevent detection) may be used for galls vi situ, ^Yithout 

 removing them from the plant. 



Several galls are well-known, including the " Bedeguars " of 

 the wild roses, produced by various species of Rhodites, the 

 '' Spangle-galls " by various species of Neiirotenis, the " Oak- 

 apples " of Andricus te?'minalis, and the Avoody, marble-like 

 oak-galls of Cynij)s Kollari, so very recently introduced into 

 Britain. The rapid diffusion of the last-named after its intro- 

 duction is only paralleled by that of Dreissena polymorpha, 

 the Zebra Mussel, and of Elodea canadensis, the American 

 Water- Weed. Mr. Smith writes me, June 28, 1878, that 

 " Cynips Kollari was introduced upwards of thirty years ago, and 

 for some time was only found in Devonshire, and was known 

 generally by the name of the Devonshire gall." 



Some attention has been paid by Yorkshire Entomologists 

 to this family, or rather to galls in general. Amongst others 

 the late Wilson Armistead of Deeds, contemplated the 

 collection of materials for an illustrated work on the subject. 

 A case of galls and their producers was depositedby him in 

 the Deeds Museum, where it may now be seen, although 

 somewhat deranged from neglect. The Rev. T. A. Marshall, also, 

 for some time, resided in this county, at Dastingham, near Picker- 

 ing. And I believe that Mr. Peter Inchbald, of Hovingham, near 

 York, has studied galls with some attention, though for the most 

 part, as he tells me, he has devoted himself to the dipterous galls 

 of the gall-gnats (Cecidomyidae), with which he has been unusually 

 successful. It is much to be wished that the information possessed 

 by the two latter gentlemen, or left in Mr. Armistead's papers, 

 should be forthcoming for the 'Transactions' of this Union, 



Mr. Fitch tells me that if any members care to send him (to 

 Maldon, Essex) the galls collected, with notes of locality and date, 

 &c., he will supply the names of the makers. He also states that 

 he has no doubt but that the more generally distributed species 

 are to be found in Yorkshire; he has had them all from Nottingham- 

 shire ; the only desideratum is the recorder. Mr. Inchbald knows 

 many Mr. Fitch is sure, but the only one actually sent by him is 



D3. 



