loo 



BRITISH GALLS 



secondary veins become considerably elongated, but their 

 elongation is arrested by the rigid margin of the leaf; conse- 

 quently, the leaf becoihes contorted in a sinuous manner, 

 forming a regular series of pleats and puckers. 



The " nail-galls " of Lime leaves resemble tintacks driven 

 through the leaf to the head from below. They are very 

 common. If an inspection of their tenants is desired, they 

 must be gathered in the early state, while green or yellowish- 

 green. Sometimes the margin of a Lime leaf is rolled 

 upwards, and the roll lined with a felt of hairs, conditions 

 caused by the presence of the mite Eriophyes tetratrichus. 



Fig. 22 — Lime Leaf with Galls caused by the presence of 



Eriophyes tiliae. (1/2.) 

 Fig. 23— Section of a Gall, showing the Cavity lined with 



Hairs. (3/1.) 



We often find Hawthorn leaves in summer-time with the 

 margins of the segments more or less rolled inwards, some- 

 times to such an extent that they resemble a spike. They 

 iare easily recognizable by the discoloration of the attacked 

 part ; the roll is lined with hairs. This gall is caused by Erio- 

 phyes ^oniothorax. It is the Erineum clandestinmn of Greville. 



Allusion must now be made to some mite-galls of interest 

 on account of their rarity in this country'^ 



I was delighted to find in June, 1909, on the slopes of the 

 headland to the south of the beautiful old fishing village of 

 Brixham, the Common Bindweed bearing a pretty gall 



