138 NEUROTERtIS APRILINUS. 



This is commonly known as the " button gall." 



These galls are found from July onwards. The 

 imagos escape in April, and lay their eggs in the leaf- 

 buds. 



Inquilines. — Synergus TscheM, Mayr, in April. 



Parasites. — Torymus fuscicrux, Giraud. Walker 

 (Zool., iv, 145) records Gallimome mutabilis, Platyme- 

 sopus tibialis, Eurytoma curta, E. sethiops, Boh., Eu- 

 pelmus urozonus ; and Fitch (Ent. 3 x, 69) Pleurotropis 

 sosarmus. 



Sexual Form. — Black ; antennse brownish, the second and the greater 

 part of the third yellow ; legs yellow ; the coxae, except at apex, and 

 femora more or less black ; the trochanters and hind tibiaa sometimes 

 brownish. Wings hyaline, a very faint smoky cloud at end of first 

 cubital cellule. Vertex aciculated; mesonotum smooth, shining, the 

 parapsidal furrows generally obsolete ; scutellum smooth, shining, 

 scarcely aciculated. 



Length 1*5 — 2 mm. 



Gall. — Irregularly semicircular or oval, 2 — 3 mm., 

 pale green ; a swelling in the leaf, projecting from 

 both sides; on the top in the centre is a small raised 

 point, from which radiate to the circumference minute 

 keels. The under surface bears no knob, nor has it 

 distinct keels. It is raised on both sides hardly \ mm. 

 from the surface of the leaf. There is no inner gall, 

 and the larva escapes by the upper side. 



The gall is found at the end of May and in June, 

 and the female oviposits in the tender leaves. 



Common and of wide distribution. 



6. Neuroterus aprilinus. 

 PI. V, fig. 2. 



Spathegaster aprilinus, Gir., Verb. z.-b. Ges. Wien, 1859, 363; 

 Mayr, Eichengallen, 32, pi. iv, fig. 42 ; 

 Europ. Cyn., 37 ; Adler, Z. wiss. 

 Zool., 201, pi. x, fig. 19 a; Licht., 

 Cyn., 65, pi. xi, fig. 19 a ; Beyerinck, 

 Beob. u. d. ersten Entwickel. einiger 

 Cynipiden Gallen, p. 138. 



