306 



Insect Pests. 



Abroad it occurs in all the northern European States, Germany, 

 France and Italy. 



TREATMENT. 



Spraying with hellebore wash or arsenical wash when the larvae 

 are abundant is certainly advisable in nut plantations when the 

 young larvse are at first seen, as they cause great havoc, and the 

 parasites mentioned above do not do any good until all the damage 

 is done. 



REFERENCES. 



(1) Theobald, F. V. Report on Economic Zoology for year ending April 1st, 



1906, p. 42 (1906). 



(2) Theobald, F. V. Report on Economic Zoology for the year ending 



April 1st, 1907, p. 60 (1907). 



(3) Cameron, P. ' A Monograph of British Phytophagous Hymenoptera,' 



vol. II., p. 35 (1885). 



THE NUT CATKIN MIDGE. 

 (Cecidomyia coryli. Kalt.) 



The male catkins of the filbert, cob and hazel nuts are often 



attacked by the small 



[W. H. Hammond. 



FIG. 205. MALE CATKINrQF NUT 

 ATTACKED BY CECID LARV.K. 



maggots of one of the gall-flies or Ceci- 

 domyidse. 



The mature insect I have been unable 

 to breed so far, nor do I know of any 

 description of it. It is not recorded by 

 Yerrall (1), yet it is widely distributed, 

 being very abundant in Kent, Sussex, 

 Middlesex, and I have found it in Here- 

 fordshire and Devon. 



The damage done by it does not 

 appear to be generally very serious, but 

 Mr. Hammond of Canterbury wrote me 

 in 1899 that it was so abundant in that 

 part of Kent that it could be found on 

 every nut tree in large numbers. 



Weitenweber (2) and Kaltenbach (3) 

 refer to it in Germany. 



REFERENCES. 



(1) Verrall, G. H. 'List of British Diptera ' 

 (2nd ed.), p. 7 (1901). 



(2) Weitenweber. ' Lotos,' p. 143 (1868). 



(3) Kaltenbach, J, H. ' Pflanzenfeinde,' p. 637 (1874). 



