ANDRICUS TESTACETPES. 71 



past most of the hairs fall off ; they ma}' also be easily 

 removed by leaves or twigs rubbing against them. 



The gall is usually surrounded at its base by small 

 leaf-scales ; sometimes attached by a rather long and 

 stout peduncle ; almost always surmounted by a styli- 

 f orm ]3rolongation, which may be two thirds the length 

 of the larval chamber, or even as long. 



The style varies much in shape, sometimes quite 

 straight, sometimes considerably curved, ending bluntly 

 or bearing a small papilla; growing from the centre 

 of the apex of the larval chamber, or somewhat on one 

 side. 



The larval chamber is large, the walls very thin. 

 Occasionally the exterior will be slightly constricted 

 near the base; sometimes longitudinall}' striated; 

 almost always glossy when the hairs are removed, 

 and woody and hard in texture. 



Seldom two galls on the same twig, very rarely 

 more than two. Some remain attached all through a 

 mild winter, others fall at the slightest touch. 



Andricus testaceipes, Hartig. 

 (Plate XVI.) 



Andricns Sieholdii, Mayr ; A. testaceijjes, Mayr, AcTler, Liclit., 

 Kalt., Cameron. Mosley. 



English name of gall. — " The Leaf-vein Gall." 



Position of gall. — On the petiole, under surface of mid-rib, and 

 its offshoots. 



Manner of growth. — Gi-labrous, single, glossy, imbedded. 



Colour. — Green. 



Average dimensions of a mature specimen. — Length, 

 2 mm. ; In'eadth, 1 mm. 



May be sought during the months of July to September. 



Growth is complete by the end of August. 



The typical condition of the gall is unilocular and unilarval. 



The larva pupates in the gall. The imago emerges during 

 August and September. 



Parasite, No. 56. 



Alternate agamic generation : Aj;ihilothra- SiehoJdi, Hartig. 



