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daphnids, ot which they caught and demolished large specimens. 

 The daphnids are said to have served as food all through the nymph 

 stage after the protozoa became insufficient. 



A bibliography of 23 titles relating to the biology of the Odo- 

 nata is appended. 



W. F. RANKINE. The Wasp-Pest. The Gardeners' Chronicle,}^ 

 16, 1910, p. 39. 



There is very little to be urged in defence of the common Wasp. 

 Certainly it acts as a pollinating agent, and also, at certain seasons, 

 is responsible for the removal of certain insect pests. When the 

 Wasp-queens are providing food for their first batch of maggots they 

 prey widely upon many forms of larvae. 



The real trouble comes in Autumn, when the broods hatch, and 

 the Wasps attack ripening fruits. 



Benzoline is very effective in destroying the nests. Soak the 

 nests and give fire. 



Cotton wool, soaked with a solution of Potassium Cyanide, and 

 put in the burrows, is a method useful for destroying Wasps. 



CECIL WARBURTON. Annual Report for 1909 of the Zoologist. 



Journal of the R. Agr. Soc. of England, Vol. 70, 1909, pp. 355-361. 



Corn crops. A remarkable feature of the season was the extensive 

 failure of the oat crop chiefly due to the frit fly (Oscinus frif) though 

 eel-worm disease ("tulip root " - Tylenchus devastatrix] was also 

 prevalent and the "leather jacket" grubs (Tipulae] did consider- 

 able harm. 



The difficulty with corn pests is that when their presence is 

 observed the harm is almost always already done, and it may be 

 said that remedial measures as a rule are impossible, and only pre- 

 ventive measures remain. The first point in connexion with these 

 is to ascertain the whereabouts of the pest when the crop is carried, 

 whether it is removed with this or left behind in the stubble. The 

 Hessian fly (Cecidomyia destructor] for instance is to a great ex- 

 tent carried away in the straw. The Frit fly on the contrary 

 remains in the stubble. The only way to destroy them completely 

 would be to plough in deeply in June, which should be done in 

 case of a very bad attack, where the chances are small of having 

 a crop worth reaping. Finally early sowing is recommended where- 

 ever possible as it is the late sown crops which suffer most. 



