104 



Use of Bisulphide of Carbon. 



[may, 



the longitudinal ridges of the wing-covers are rows of 

 punctures. The legs are pale red, and the antennae of the 

 beetle are somewhat thickened towards the top. 



The appearance of the magnified grub is well shown in the 

 illustration. The dark coloured head has brownish jaws. The 

 three segments behind the head each carry a pair of legs ; on 

 the upper surface of these thoracic segments is a dark trans- 

 verse curved line, whilst down the back of the remaining 

 segments there are two rows of large square spots, with rows 

 of smaller spots below down each side. The body ends in 

 two processes. 



Some grubs sent to the Board of Agriculture early in 

 October, 1904, measured over one quarter of an inch, and 

 were not full-fed. 



Remedial Measures. — The complete life history of this beetle 

 is not yet known, but in the observations made up to the 

 present it has been found that turnips grown in a field 

 adjoining a field infected in the previous year are those most 

 likely to be attacked. In the rotation, then, as far as prac- 

 ticable, turnips should be sown as far as possible from the 

 infected field. In fighting the pest the most successful measure 

 has been the application to the crop of stimulating dressings ; 

 1 cwt. of nitrate of soda per acre proved satisfactory on that 

 portion of the field least infected. 



R. Stewart MacDougall. 



The use of bisulphide of carbon as a remedy for wireworms 



in flower-beds and borders is suggested in the Board's leaflet 



(No. 10), and it may be noted that this 



J? S £ °£ bisulphide SUD stance has been used very successfully 

 ot Carbon against 



Wireworms. on a l ar ge scale against the vine phylloxera, 



and there are excellent records in its favour 



against the maggots which attack cabbage. The character of 



the soil determines the rate at which the fumes diffuse through 



the soil. On heavy clay soils, especially if these be soaking wet, 



diffusion is very slow ; on clay soil, moist but not too wet, 



diffusion takes place more quickly ; and diffusion is most rapid 



