152 



FOREST ENTOMOLOGY. 



and may not inaptly be compared to a miniature rifle-bullet with 

 longitudinal ridges added on. 



I have not succeeded in rearing the fly, which Adler says is very 

 difficult, and does not appear until the following April. It is very 

 common in Alnwick parks. 



Aphilothrix albopunctata (Schltdl.) 



The gall of this species is a very pretty little object, and is 

 formed in the bud (fig. 147). It somewhat resembles a small 



acorn. It is green, spotted with red, and 

 is about 5 to 6 mm. long. The larvae are 

 gregarious, and the gall is not chambered. 

 The galls were very common in High 

 Legb, Cheshire, and were found in May. 

 The flies hatched out about June of the 

 same year. 



Andricus ramuli (Linn.) 



This gall is known as the cotton gall, as it 

 occurs on the flower and resembles a ball of 

 cotton-wool (fig. 148). The hairs are inter- 

 woven so as to form a sort of felt. The galls 

 lire many-chambered, or polythalamous. This 

 is by no means a very common gall. I have 

 found it twice, once in Wales, in June 



1901, and again in the Alnwick parks, July 1898. The flies 



hatch out in July. 



Fig. 147. Galls of Aphil- 

 othrix albopunctata. 



Aphilothrix fecundatrix, Htg. (Adler). 

 Andricus fecundatrix, Mayr (Cameron). 



This gall is known as the artichoke gall. It very much resembles 

 a hop-flower, with imbricated scale. At first it is of a green colour, 

 but becomes brown with age. In collecting those galls when mature 

 much care is necessary to obtain the imagines. The real gall is a 

 small acorn-shaped body within these scales, but so very loosely 



