337 

 MIDGE -GALLS OF YORKSHIRE. 



RICHARD S. BAGNALL, F.R.S.E., F.L.S. AND J. W. H. HARRISON, 

 D.SC, F.R.S.E. 



For the past few years we have devoted a considerable portion 

 of our leisure to the study of the Zoocecidia of the British 

 Isles, during the course of which numerous expeditions were 

 made into various Yorkshire localities. Temporarily, how- 

 ever, our work in that county has come to an end, so that we 

 deem this a suitable time for putting on record the results 

 of those journeys as far as the Cecidomyidae or Gall -midges 

 are concerned ; our observations on the Eriophyid mites 

 will afford material for a subsequent paper. 



Group Lasiopterariae. 



Clinorrhyncha chrysanthemi H. Loew. Sparingly on achenes of Alatricaria 

 inodora and Anthemis cotula. Middlesbrough district. 



C. inil'.efolii Wachtl. Feeds on Achillea Millefolium and A. Ptavmica 

 achenes. Very rare, Eston, Ayton. 



Trotteria umbelliferarum Kieff. On Anthriscus. Rare, Gunnergate. 



Lasioptera rubi Heeger. Affects stems of various Rubi. Nunthorpe, 

 Saltburn, Scarboiough ; not common. 



Group Oligotrophariae. 



Misopatha ptarmicae Vallot. On both species of Achillea. Not common ; 



Middlesbrough area. 

 M . syngenesiae H. Loew. On Anthemis and Matricaria. Waste places, 



edges of fields ; fairly well distributed. 

 Rhopaloniyia millefolii Mchl. On yarrow, Redcar. 

 OligotropJiiis bursarius Bremi. Galls leaves of Glechoma hederacea. 



Generally distributed. 

 O. fagineus Kieff. Forms a parenchymatous gall on beech leaves. Not 



common ; Leeds. 

 O. juniperinus (L.). On juniper, near High Force. 

 O. hartigi Lieb. Similar to O. fagineus, but on various species of Tilia. 



Gunnergate, Leeds ; rather rare. 

 O. reaumurianus F. Loew. Forms a neat gall on leaves of Tilia. Rare ; 



Gunnergate. 

 O. tympanifex Kieff. Somewhat like O. fagineus, but on hazel. Guis- 



borough, Eston, Ayton, Saltburn, etc. 



0. ulmi Kieff. Also parenchymatous. On Ulmus campestris and U. 



montana. Plentiful where there are old elms. 

 Schmidtiella gemmarum Riibs. On juniper, near High Force. 

 Mikomyia coryli Kieff. On hazel leaves. Well distributed but far 



from common. 

 Semudobia betulae Winn. Affects fruit of Betula. Common, but local. 



Eston, Lonsdale, Kildale. 

 lieomyia capreae Winn. Leaves of Salices of the Caprea group. Piac- 



tically everywhere. 



1. major Kieff. Somewhat like /. capreae, but rarer. At present only 



from Salix aurita and S. cinerea. Redcar, Great Ayton Moor. 



Janetiella lemeei Kieff. Forms a characteristic gall on midrib and nerves 

 of elms in June. Local, but very abundant where it does occur. 

 Bardsey, near Leeds. 



Mayetiola avenae Marchal. Galls stems of Arena. Very rare ; Nun- 

 thorpe. 



1921 Oct. 1 



