48 TRANSACTIONS OF THE 



a few of its local habitats. At present tliere does not appear 

 to be any material check upon its increase, for although birds 

 at first destroy the larvse, yet, in course of time, leave them 

 alone, not finding them suitable food. Nevertheless I have 

 reared from one of the galls a large Synergus, evidently the 

 same species that was bred from the gall of A. radicis {vide suprd), 

 and no doubt, as other inquiliues and parasites will become aware of 

 its presence, their number will be kept within due limits. They 

 show a partiality for small shrubby oaks, but I have also noticed 

 the galls upon the topmost twigs of a tree about thirty feet high. 



Biorhiza aptera, Fab. — For a gall of this species I am indebted 

 to Mr. Barlas, who picked it up at Dalreoch. It was of an oval 

 form, dark-coloured, and rough outside, white and smooth within; 

 a thin partition in the centre divided it into two cells, in each of 

 which was a specimen of the apterous maker. Usually the galls 

 are monothalamous, i.e., one-celled. 



B. renum, Hart. — The minute, reniform, pale-green galls are 

 situated in clusters on the veins on the underside of oak leaves; 

 and late in autumn swell up to more than double their previous 

 size, and fall to the ground. The galls are common in the autumn 

 in Cadder and Kenmuir woods. 



Neuroterus numismatis, Oliv. — The maker of the well-known 

 "silky button galls," which occur on the underside of oak leaves 

 nearly everywhere. 



N. lenticularis, Oliv. — The equally well-known "oak spangle" 

 galls of this species are even commoner than the " button" galls, 

 and are frequently found on the same leaf with them. Kenmuir, 

 Cadder, Langside, etc., are good stations for both. 



N. fumipennis, Hart (?). — Mr. Traill describes the supposed galls 

 of R. fumipennis (Scot, Nat., ii., 127), and similar galls I have 

 noticed at Cadder and Kenmuir. The insects reared therefrom 

 (which I have received from Mr. Traill), however, appear to be 

 only iV. lenticularis ; at least I cannot distinguish any difference 

 between the two ; and the Rev. T. A. Mai'shall also thinks tliat they 

 are the latter species. The galls certainly differ both in habit and 

 form from the common spangles. 



N. ostreus, Hart. — The galls are not unfrequent at Kenmuir and 

 Cadder during August and September. 



Andricus curvator, Hart. — The galls are found in abundance at 

 Cadder, Langside, Kenmuir, etc., aud are generally distributed 



