122 



The Galls of Essex ; a Contribution to a 



Brassica oleracea, L. stem. The 

 stock is covered with irregular sweUings 

 or knots ; each gall contains a single 

 larva, but frequently a number of galls 

 coalesce and form a composite gall as 

 large as a walnut. The larv» leave the 

 galls in early spring and pupate in the 

 ground. The destructive cabbage-gall 

 beetle. Ceuthorhynchus sulcicollis, 

 Gyllenhal. (Fig. 2). 



Brassica campestris, L. Koot- stock. 

 The turnips and swedes are most com- 

 monly disfigured by hard swellings on 

 the surface of the " roots " ; each of which 

 contains the larva of the beetle, but 

 possibly of a different species from the cabbage-gall beetle. 

 The larva in the white turnips and swedes differ in colour and 

 slightly in structure. Pupates in the earth. Ceuthorhynchus 

 SULCICOLLIS, Gyllenhal. 



Brassica Sinapistrum, Boiss {Sinapis arvensis, Eng. Bot.). 

 Boot. The stalk is galled just below the ground, causing an 

 irregular, round, white, hard, swelling, wdiich contains gene- 

 rally but a single yellowish-white larva ; but two or three 

 galls sometimes coalesce on the same plant. The larva 

 pupates in the gromid. Ceuthorhynchus assimilis, Paykull. 



Eaphanus Eaphanistrum, L. Koot. Similar swellings, 

 just about the surface of the ground, to the charlock galls. 

 Ceuthorhynchus assimilis, Paykull. 



Fig. 2. 

 CeuthurJi. .sulcicuUiti. 



Caryophyllace.e . 



Stellaria Holostea, L. Apical leaves. The terminal 

 leaves are smaller, hardened and closely imbricate, generally 

 discoloured. Brachycolus Stellarle, Hardy. Mr. Hardy 

 states (Buckton's ' British Aphides ' ii. 148): — "During the 

 summer the ApJiis migrates from the stitchwort to one of the 

 grasses, Holcus viollis. Here it likewise revels in the centre 

 of a tuft of leaves, for these leaves, being prevented from 

 receding, embrace each other at then- bases like those of a 



