478 



condemnation of its habits, but a close study of its life-history shows 

 that this is not justified. Fertilised females hibernate during August 

 and September, and commence nest-building at the beginning of 

 October. Several days after o\nposition the larvae hatch and after 

 being fed on sugary substances for a few days, receive a diet of insects. 

 It is during this larval period, lasting 14 to 18 days, that the hornet 

 proves its economic value, reducing considerably the number of 

 insects injuring the cane crops, and playing an important part in the 

 control of cutworms and army-worms, grasshoppers, crickets and flies. 

 After a pupal period of about 15 days the adults emerge and the nests 

 increase in size until the end of April. Mating occurs during June and 

 July ; by the end of July all the males are dead and the females begin 

 to hibernate. In certain localities where the cane is thrashed during 

 the season when the hornets' nests are at their maximum size, a good 

 deal of trouble and expense is incurred in sending labourers encased 

 in thick canvas to destroy the nests before thrashing the cane. Hornets' 

 nests are frequently attacked and destroyed by enemies, probably 

 lizards, spiders and ants, which feed on the larvae. 



Metcalf (Z. p.). Biological Investigation of Sphe.nophorus callosus, 

 Oliv. — North Carolina, Agric. Expt. Sta., W. Raleigh, Tech. Bull, 

 no. 13, January 1917, 123 pp. 68 figs. 1 plate. [Received 23rd 

 August 1917.] 



This bulletin is an amplification of one that has been previously 

 abstracted [see this Review, Ser. A, v, p. 445]. 



Williamson (W,). Fall Treatment for Insect Pests of Field Crops. — 

 Minnesota Insect Life, St. Paul, iv, no. 5, 1st August 1917, p. 3. 



Autumn ploughing and harrowing are advocated for the control of 

 grasshoppers, wireworms, white grubs, cutworms, Hessian ^j and 

 many lesser pests, and the method suited to each is described. The 

 burning of weeds and rubbish after harvest is recommended against 

 Hessian fly [Mayetiola destructor], chinch bugs [Blissus leucoptera], 

 wheat straw and joint woTTas[Meromyzu americana and Isosoma tritici], 

 army- worms and stalk-borers. Clover pests can be controlled by keeping 

 down self-sown clover and by lightly pasturing clover in the autumn. 



Change Wheat Storage Methods. — Wkly. Press. Bull. Penns. Dept. 

 Agric, Harrisburg, ii, no. 32, 9th August 1917. 



The Pennsylvania Department of Agriculture is urging farmers to 

 avoid storing their wheat after harvest in warm, well-built barns, 

 w^hich offer ideal conditions for the rapid development of the Angoumois 

 grain moth [Sitotroga cereaMla], and is advising them to have their 

 wheat threshed as soon after the harvest as possible. Wheat that is 

 known to be infested before threshing should be fumigated Avith carbon 

 bisulphide. 



Snell (J.). An Invasion of the Caterpillars of the Antler Moth into 

 Yorltshire. — Jl. Bd. Agric, London, xxiv, no. 5, August 1917, 

 pp. 523-526, 1 fig. 



The damage caused by the antler moth [Charaeas graminis, L.] in 

 Yorkshire in June, 1917, was very similar to the infestation in 



