The Scottish Naturalist. 127 



lothrix) radicis Fab. For a specimen of this gall, from near 

 Glasgow, I am indebted to Mr. Cameron, jun. It consists 

 of a swelling on the root, made up of a mass of oval 

 cells irregularly grouped, the walls coalescing more or 

 less. The wall of each cell is very thin and compact, and 

 the cavity is pretty large. Externally, each cell is about \- 

 inch by |-inch. Outside the mass of cells is a layer of 

 compact woody tissue, outside which is a loosely compacted 

 layer, (k) Gall of Biorhiza renum H. The galls are at- 

 tached to the chief veins on the lower surface of the leaf, 

 usually in pairs, one on each side of the vein. For a time 

 they remain small ( VI -inch by |^-inch), and distinctly reni- 

 form, but in October they swell up to several times their 

 former bulk, become nearly globular, and readily fall oft" the 

 leaf. They are. smooth, naked, and green. They are mono- 

 thalamous, and thin-walled. Usually many occur on a leaf. 

 They remain all winter on the earth, and produce their oc- 

 cupants in spring. Abundant at Dunkeld in September, 

 and at Parkhill, near Aberdeen, in October, (l) Galls of 

 Neuroterus fwnipennis H. ? The insects reared from them 

 this spring do not agree with Marshall's description (E. M. 

 M., iv. p. 125), but the galls agree with those of this species. 

 They are the size and shape of " oak spangles," but are flat- 

 tened, with the centre slightly depressed. They are smooth, 

 with hardly any hairs on their surface ; usually bright green, 

 but when on the upper surface of the leaf they are bright 

 red ; they become purple when dry. They are monothala- 

 mous. Usually they are scattered over the lower surface of 

 the leaf, but occasionally occur on the upper. I have never 

 seen them crowded together like the common "oak-spangle." 

 Common about Dunkeld in September, and Mr. Roy tells 

 me he has seen similar galls on Deeside. (m) Galls of 

 Neuroterus ostreus H. occurred sparingly about Dunkeld in 

 September, attached to the chief veins or midrib of 

 the leaf below. They are usually ovate (^-inch by 

 ^'f-inch; they are smooth, naked, and light-green, usually 

 spotted with red. They are thin- walled and monothala- 

 mous. At the point of attachment, two valve-like mem- 

 branes project (one on each side), the remains of a skin 

 which covered the gall in its early stage of development 



