405 

 PLANT GALL FORAY AT LEEDS. 



WM. FALCONER, F.E.S. 



The members of the Union interested in plant galls met for 

 the second time at Leeds on Saturday, September 17th, to 

 continue their investigation of the Roundhay Park and Adel 

 Moor districts. In the morning the party traversed that part 

 of the park lying between the Canal Gardens and the far end 

 of the Gorge ; in the afternoon, much the same ground was 

 covered as on the previous occasion.* At neither meeting 

 was the productive-looking valley below Adel Bog investi- 

 gated, lack of time in one instance, and the approaching dusk 

 in the other, preventing any search there. 



At the end of the ramble, no fewer than 76 different forms 

 had been collectively recognised as affecting 34 different 

 species of plants ; 59 of them are recorded below, all but 6 

 (now found in other parts of the route) being additions to the 

 May gatherii:kg.* Included were one or two noteworthy finds. 

 Asterodiaspis quercicola Bche, of which I know no other 

 northern records than the two given in the list, may easily, 

 from its inconspicuousness, be overlooked, but in all proba- 

 bility, it will be found elsewhere in Yorkshire if properly 

 searched for in its season. It seems to prefer scrub by the 

 roadside, and young oaks in woods, the habitats respectively 

 in the two recorded county stations. Specimens which I 

 have under observation at home appear to be developing, the 

 outline is less circular and the covering membrane is becoming 

 darker in colour and bulging outwards. Perrisia galeobdolon- 

 iis Winn., which again occurred freely in the Gorge, is stated 

 in the lists of Messrs. Bagnall and Harrisonf not to occur in 

 the north of England. I have met with it also at Thunder 

 Bridge, Huddersfield. P. populeti Riibs. is new to the 

 county, but is on record for Northumberland and Durham. 

 In Roundhay Park, as I have seen in localities elsewhex-e, 

 some leaves of the oak have their midrib slightly swollen and 

 twisted, usually in the apical half ; there is often a fracture 

 at this point, and beyond it a pleating of the blade, and an 

 overlapping and torsion of the lobes. So far I have not 

 discovered the agent concerned (if there be one), and this is 

 a question which needs clearing up. 



Meetings of the Plant Gall Committee will be held next 

 year at Askham Bog and Harewood, if suitable arrangements 

 can be made. 



* See The Naturalist, August 1921, pp. 269-272. 



t Trans. Ent. Soc, London, issued 1918, pp. 348-426, and Nat., 

 October 1921, pp. 337-341- 



