SPATHEGASTER BACCARUM. 129 
A few of the large outer leaf scales of the bud 
surround the base of the gall and assist in retaining 
it in position. The greater part of the upper portion 
of the gall is bare except for a few of the small inner 
leaf scales which adhere to it. The gall does not fall 
to the ground. The structure is of a vesiculate nature, 
with thin, soft, and sappy walls. The interior forms 
a large larval chamber. There may be two or three 
larvee, each occupying a separate cell, but a larger 
number of cells generally denotes the presence of 
inquilines. The cells are oviform in shape, and 
arranged perpendicularly on their own longitudinal 
axis. They are large in comparison with the size of 
the larva. The arrangement is sometimes indicated 
on the exterior of the gall. 
The gall occupies about two-thirds of the bulk of 
the bud. In shape it is an elongate ovoid, flattened 
on the inner side for about four-fifths of its entire 
length. It is found more plentifully on stub-oaks of 
about five to seven years’ growth, than on full grown 
trees. 
Spathegaster baccarum, Linn. 
(Plate LITT.) 
Cynips Quercus baccarum, Linn.; Spathegaster interruptor, 
Hartig; S. baccarwm, Mayr, Fitch, Miller, Adler, Marshall ; 
Neuroterus baccarum, Mayr; N. lenticularis, Cameron. S 
English name of gall.—< The Currant Gall.” 
Position of gall.—On the staminate catkins, and on the leaves. 
Manner of growth.—Glabrous, glossy, gregarious, succulent, 
globular. 
Colours.—Pale green, greenish-yellow, pink, red, purple. 
Average dimensions of a mature specimen.—On catkin : 
Girth, 7mm. On leaf: Girth, 10 mm. 
May be sought during the months of May and June. 
Growth is complete by the end of June. ; 
The typical condition of the gall is unilocular and unilarval. 
The larva pupates in the gall. The imago emerges during 
June. oy Moy , F 
