202 



during the day and become active at dusk. The adults hibernate 

 in sheltered places such as barns or haystacks. Many larvae die 

 during a continued frost, and numbers are killed by parasitic insects. 

 The best method of controlling the numbers of P. scahra is to cut the 

 crop so as to remove the food supply at the moment when the cater- 

 pillars are most abundant. Clean cultivation and the destruction of 

 weeds in the vicinity should also be practised. The hopper-dozer 

 might be used with advantage in the case of particularly bad outbreaks. 



Phillips (W. J.). The Wheat Jointworm and its Control.— C7.S. Dept. 

 Agric, Washington, D.C., Farmers' Bull. no. 1006, October 1918, 

 14 pp., 17 figs. [Received 7th March 1919.] 



The Chalcid, Isosoma (Harmolita) trifici, Fitch (wheat jointworm), 

 ranks next to the Hessian fly [Mayetiola destructor] as a wheat pest 

 in the wheat-growing States east of the Mississippi and in parts of 

 Missouri. The method of infestation is described and illustrated, the 

 injury causing the wheat stems to bend over to such an extent that 

 the heads are lost when the wheat is cut. The life- history, the damage 

 done to growing wheat, and the control exercised by natural parasites 

 have been described in a previous paper [see this Review, Ser. A, 

 V, p. 213]. This pest can be controlled in Virginia, Tennessee and 

 Kentucky by ploughing in the wheat stubble deeply directly after 

 the harvest. It is suggested that rye should be substituted for wheat 

 in the more northern States, such as Michigan, where injury is severe. 



Ealmbach (E. R.). The Crow and its Relation to Man. — U.S. Dept. 

 Agric, Washington, D.C., Bull. no. 621, 16th February 1918, 92 

 pp. [Received 7th March 1919.] 



Animal food forms only 28-14 per cent, of the yearly sustenance 

 of the adult crow {Corvus brachyrhynchos), but it is of greater economic 

 importance than the vegetable portion, the crow being primarily 

 carnivorous and the vegetable matter being eaten more from necessity 

 than from choice. The greatest proportion of animal food is consumed 

 in May (5244 per cent.) followed by a uniform decrease till the 

 minimum (11 per cent.) is reached in February. The figures quoted 

 in this paper have resulted from the examination of the stomachs 

 of 1,340 adults and 778 nestlings collected in 39 States, the District 

 of Columbia, and several Canadian Provinces, 



These investigations have shown that insect food is taken by 

 adult crows in every month of the year, though in January it amounted 

 to only 1-29 per cent., the insects identified belonging to 12 orders. 

 The diet of nestling crows comprises 83*49 per cent, of animal food, 

 of which insects form the major portion, 48-36 per cent. Scarabaeid 

 beetles, especially Lachnosterna (Phyllophaga) spp., are the most 

 important Coleoptera eaten, both by adults and nestlings. In the 

 former case they constitute 4-28 per cent, of the annual food, and in 

 the latter, the beetles and their larvae often form the sole diet ; hence 

 the effect of the presence of this bird on May beetles is of the greatest 

 importance. Other Scarabaeids eaten by both adults and nestlings 

 are Euphoria inda, occasionally injurious to ripening fruits, especially 



