ROEBUCK : ON YORKSHIRE HYMENOPTERA. 3 1 



Family C YNIPID.^— Gall-flies. 

 As with the Sawflies, this group is not elucidated by any 

 complete work upon the British species, and the numerous papers 

 upon galls and gall-makers which have appeared of late years are 

 scattered through a variety of journals and publications. As to the 

 identification of species (the general works not being forgotten), the 

 most important papers are those by Hartig (1840 to 1843), Giraud 

 (1859), Schenck (1865), Schlechtendal (1870), Marshall (E.M.M. 

 1867-8, iv.), Miiller (Ent. Ann. for 1872) and Fitch (who pub- 

 lished in the Entom. 1874 to 1878, vols, vii to xi. inclusive, a 

 series of translations of Dr. G. L. Mayr's work on the European 

 Oak-galls and the insects which inhabit them, with additional notes 

 by himself; the concluding paper giving full references to the 

 articles above mentioned of Hartig, Giraud, &c.) Some very 

 valuable papers on American species were published by Osten 

 Sacken, Walsh and Bassett in the first four volumes of the 

 Proceedings of the Entomological Society of Philadelphia. 

 For an account of the literature of the parasitic Cynipidse 

 refer to p. 121 of the Rev. T. A. Marshall's paper in the Ent. 

 Ann. 1874, where the monographs are distinctively marked. A list 

 of gall-bearing British plants is given by Kidd and Miiller (E.M.M. 

 Oct. 1868, V. 118-120, Feb. 1869, v. 216). A synopsis of the 

 genera of Cynipid^ is given by Dr. Forster in the 19th vol. of the 

 Vienna 'Verhandlungen,' 1869. 



The number of British species of this group can hardly as 

 yet be considered sufficiently know^n. The Rev. T. A. Marshall 

 in the Ent. Ann. for 1874, p. 138, enumerated 41 species. In 

 the Entom., Feb. 1877, x. 27 to 31, Mr. E. A. Fitch gave a 

 summary of new and rare gall-producers observed in Britain since 

 1872, in which he mentioned 19 Cynipidse, besides insects of 

 other groups. The oak-tree is unusually subject to galls, and 

 seems to afford them a lodgment in every part of its system, both 

 above and below the surface of the ground. In his notes 

 published in 1867 and 1868 (E. M. M. iv.) Marshall described 14 

 oak-species as indigenous. Ten years' work by Fitch, Cameron, 

 Inchbald, Rothera, &c,, have produced such good results that in 



