OF EPPING FOREST. 165 Imago. Colour: Reddish yellow. Antennae: Dark, basal joints pale yellow. Thorax: Pubescent and shagreened. Pro-and meso-notum more or less dark, scutellar foveae and centre of medium segment, black. Abdomen; Third segment impunctate. Legs: Pale yellow; base of coxae, hind tibiae and tarsi, may be infuscated. Wings: Smoky, especially before the cubitus. The A. solitarius galls are found in June, July and August, maturing in September. OCCURRENCE IN EPPING FOREST. Fairly abundant. Two or three galls may occur on the same twig. First appearance noted, June 26th. I have taken this gall in Kent, Devon, Cheshire, Warwick, Salop, and Merioneth, which proves that it is widely distributed. Cameron mentions it as not uncommon in Scotland and Notting- hamshire, and it has also been taken in the Hastings district. (22). Agamic Forms. XII. Andricus seminationis. (Gir). Inquilines. Synergus facialis (Htg.) and S. albipes (Htg.) Gall. Spindle shaped, somewhat like A. callidoma and A, malpighii. They may be with or without a stalk; they are ribbed longi- tudinally and covered with short downy hairs especially near the apex. They occur either on the catkin or on the leaf. Colour: Green, the longitudinal ribs usually red. Imago. Not distinguishable in any reliable way from Andricus quadrilineatus; as in the latter, the colour varies very considerably from yellowish brown to dark brown. These galls appear usually at the beginning of June, and then, according to Adler, they fall to the ground. I have, however, found them on the catkin stems as late as the middle of October; these possibly were parasitised. They occur on the catkin stems and also on the leaf; they distort the latter and cause the former to swell. This swelling commences three or four weeks before the galls themselves appear. The flies emerge in the following April or not until the second year. The eggs are laid in the buds in the middle of April. OCCURRENCE IN EPPING FOREST. I have found these galls on a few trees only, but they were very numerous whenever they did appear, the catkin stems in