166 Knapioeed Gall-fly 



3. The life-history, ovipositor, and method of oviposition are 

 described, and descriptions and figures of the ova, larvae, and pupae 

 are given. The life-history is summarised on p. 148. 



4. It is shown that owing to the formation of galls induced by 

 larvae of V . solstitialis in the flower-heads of this weed a reduction in 

 the number of seeds is effected amounting to about 50 per cent, in the 

 heads examined. The germinative capacity of the seeds produced in 

 these galled heads was also adversely affected. In the germination 

 experiment described 60-5 per cent, fewer seeds germinated from galled 

 flower-heads of C. nigra than from ungalled ones. At a moderate 

 estimate the number of seeds rendered non-effective in galled flower- 

 heads of C. nigra is placed at 50 per cent. It is pointed out that Try- 

 paneids, whose larvae adversely affect the weeds of cultivated land, 

 may be regarded as beneficial. 



5. A short account and discussion of the recorded parasites of 

 U. solstitialis is given. 



6. Some interesting features observed in the process of gall-forma- 

 tion are referred to, and a few notes are added on some other insect 

 inhabitants of the flower-heads of C. nigra. 



BIBLIOGRAPHY. 



Banks, Nathan (1912). The structure of certain dipterous larvae with particular 



reference to those in human foods. U.S. Dept. of Agric. Tech. Series, No. 22. 

 Becker, T. (1902). Die Meigen'schen Typen der Sogen. Muscidae acalypterae 



{Muscaria holometopa) in Paris und Wien. Zeitschr. Hym. Dipt. ir. 

 Bezzi, M. (1911). Restaurazione del genere Carpomyia (Rond.) A. Costa. Boll. 



del Laborat. di Zool. Gen. e Agr. Portici, vol. v, pp. 3-33. 

 Bezzi, M. (1913). Indian trypaneids (fruit flies) in the collection of the Indian 



Museum, Calcutta. Memoirs of the Indian Museum, Calcutta, vol. iii, No. 3. 

 Boie, F. (1847). Zur Entwickelungsgeschichte mehrer Trypeta-Arten. Stettin. 



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 Brischke, C. G. a. (1882). Die Ichneumoniden der Provinzen West- und Ost- 



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 CoNNOLD, E. T. (1901). British vegetable Galls. London. 

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 DuFouR, L. (1857). Melanges entomologiques. Article ii, Urophora quadrifasciaia. 



Ann. Sac. ent. France, S'^ s6rie, T. v, pp. 53-58. 1 pi. 

 Fitch, E. A. (1872). Urophora solstitialis Linn., a gall-maker. Entomologist, 



London, vol. vi, p. 142. 

 Fitch, E. A. (1879). Trypeta reticulata, and general notes on the British gall-making 



Trypetidae. Ibid. vol. xii, pp. 257-259. 



