ON THE COMMON OAK i6i 



sion, which keeps the green tint when the rest of the gall 

 hc^s become reddish-brown. Appearing in summer ; 

 mature in October, when it falls to the ground. Imago, 

 spring. III. 



ANDRICUS CURVATOR, form COLLAR IS 233 



Syn. Andricus collaris Hartig ; Aphilothrix coUaris 

 Adler. 



Connold, Oak Galls, fig. 8 ; Plant Galls, fig. 185. 

 Houard, No. 1216. Adler and Straton, Alternating 

 Generations, pi. i, fig. 9. 



Hymen- In the axillary and terminal buds. Gall very minute, 



optera ovoid, 2 mm. long, green, becoming brown, smooth and 



shining. Appearing in May. Imago, July or August, I. 



Andricus gemmatus Adler 224 

 Connold, Oak Galls, pi. S ; Plant Galls, fig. 177. 

 Houard, No. 1297. Adler and Straton, Alternating 

 Generations, pi. i, fig. Ta. 

 " In the bark at the base of the trunk, gregarious woody 



galls, each covered with a conical operculum, fleshy and 

 red at first, which falls off at maturity, when the gall re- 

 sembles a minute cone with its point buried in the bark, 

 its base (3 to 4 mm. in diameter) slightly exposed. Around 

 the edge of the base are a series of little punctiform de- 

 pressions ; in its centre a rounded smooth swelling, within 

 which is the larval cavity. Imago, April or May, II. 



Andricus gemmatus, form corticis 225 

 Syn. Aphilothrix corticis Linn. Andricus corticis Mayr. 

 Connold, Oak Galls, pis. 19, 20a ; Plant Galls, fig. 166. 

 Houard, No. 1 291. Adler and Straton, Alternating 

 Generations, pi. i, fig. 7- 



Terminal buds of a twig remaining short and thickened, 

 causing a thick swelling (12 mm. by 7 mm.), bearing some- 

 what tufted leaves. The central cavity contains an internal 

 gall firmly fixed to the bottom; lateral twigs often grow from 

 the gall after the insect has emerged. Imago, June, I. 



Andricus inflator Hartig 226 

 Connold, Oak Galls, pi. n; Plant Galls, fig. 170. 

 Houard, No. 1205. Adler and Straton, Alternating 

 Generations, pi. \, fig. 8a!. 

 „ In a bud. Gall solitary, green, glabrous, 3 to 5 mm. in 



d anieter, seated on a swelling and surrounded at its base 

 by the bud scales, fleshy and soft beneath its outer layer. 

 It contains an internal hard, woody gall, covered with a 

 reticulated network of lines. The gall falls to the ground 

 in Octobier, and the internal one drops out. Imago m 



spring, II., III., VI. 



Andricus inflator form globuli 227 



