The Cabbage Ply. (Anthomyia brassicce.) 



(PLATE II., Fig. 2.) 



Complaints of injury to cabbages, broccoli, cauliflowers and 

 other species of brassicse were sent in during the last summer. 

 Some of these came from market gardeners in Bedfordshire, 

 Essex, Lancashire, and Surrey, who spoke of considerable 

 mischief having been caused by whitish maggots in the roots 

 of the plants which prevented them from forming heads and 

 hearts properly. One correspondent styled this an extraordin- 

 ary attack on the cabbage plants throughout the locality. In 

 other cases farmers reported that the Drumhead varieties of 

 cabbage were much injured. Swedes also were affected to 

 some extent. It was said that there was a dirty white grub 

 of a cylindrical shape in the roots, and that the plants thus 

 infested turned yellow and flagged, or in some cases died. This 

 is by no means a new pest. Curtis described it and spoke of 

 losses occasioned by it in certain years. French, German, and 

 American entomologists write of it as quite common in parts of 

 France, Germany, and America. 



DESCRIPTION AND LIFE HISTORY. 



The fly is rather larger than a house fly, and the female 

 differs rather materially from the male, as is the case in most 

 of the Antkomyidce. Unfortunately females only came from 

 the larvae sent, so that a figure of a male from life cannot be 

 given here. 



The female is of a light grey colour with sparse hairs 

 on the body, and legs also grey. Its head is clear grey and 

 the eyes very wide apart with a red coloured space between them, 

 having black hairs upon it. It has translucent wings, slightly 

 yellow at their bases. The male is ash-grey, covered with black 

 hairs. Its thorax is dark grey having three longitudinal black 

 stripes. The abdomen is lighter in colour with a rather narrower 

 black stripe down it. and three transverse black lines, so that 

 eight black spots, or patches, are formed. The wings and legs 

 closely resemble those of the female. 



These flies may be seen throughout the summer. In the spring 

 the females begin to place eggs upon the roots, as deeply below 

 the junction of the leaves and roots as they can reach. Larvae 

 come forth in about 10 days and make their way at once through 

 the cuticle of the roots, and scrape out passages within them, living 

 upon their juices and thereby checking their growth. Besides, 

 they cause decay in the roots, and young plants soon succumb 

 to this attack, 



