148 THE OAK GALLS AND GALL INSECTS 



Dryophanta taschenhergi. Very plentiful, especially growing- 

 from adventitious buds on the trunks of old trees. I have alsa 

 found some of the galls on the buds of twigs, growing quite at the 

 base of the trunk. When old, these galls lose their velvety purple 

 appearance and assume a dull brown colour, often remaining on 

 the trees for a considerable time after the insects have emerged.. 

 First appearance noted, May i8th. 



(8). Agamic Generation. II. Dryophanta longiventris. 



(Htg.) Inquilines. Synergus pallicovnis (Htg.) and S. apicalis- 



(Htg.) 



Gall. 



Found on the under-surface of the leaf arising from the leaf 

 veins. Shape : Globular, the surface often being nodulated and 

 sometimes winkled. Colour : Green to yellowish white, often 

 marked with reddish stripes. 



This gall is hard and woody, the central cavity is small and 

 the walls are thick. The top is not depressed. It is much 

 smaller and more flattened than D.folii. 



Imago. 



Very similar to Drophanta folii, the only tangible difference being in the 

 antennae, which have the 12th joint less bioad than long. There are no other 

 constant characters by which these two insects can be differentiated. 



(8.) Sexual Generation. IIa. Dryophanta similis. 

 (Adler). 



Gall. 



Very similar to D. tascJienhevgi, but more slender and 



pointed. It is covered with hairs, which are longer and whiter 



than is the case with the D. tacJienhevgi gall, which give 



the original green colour a somewhat greyish appearance. I have 



found these galls slightly purple in colour. 



Imago. 



Almost identical with D. taschcnbergi, though generally somewhat 

 darker in colour. 



Account of Generation Cycle, 

 The Dryophanta longiventris gall is very liable to parasitic 

 infestation. The perfect insects mature in November and 

 December, when they sometimes emerge, but usually they do not 

 appear until March. The date at which they leave the gall 

 depends a great deal upon the temperature. They lay their 



