APHILOTHRIX MARGINALIS. 89 
much more spindle-shaped than the previous speci- 
mens, and also distinctly ridged—a feature neither 
mentioned by him in his description of the gall, 
referred to by Cameron, nor found in my specimen. 
There may be, however, variations in mode of 
growth such as would allow each of the above to be 
representative. 
They are illustrated in Fig. 9 for comparison, and 
to assist the collector to identify any he may find. 
Aphilothrix marginalis, Schlechtendal. 
(Plate XXIV, div. A.) 
Cynips marginalis, Mayr, Schltdl.; Andricus marginalis, Mayr, 
Cameron; Aphilothriz marginalis, Mayr, Licht., Adler, Fitch, 
Mosley. 
English name of gall.—‘ The Marginal Gall.” 
Position of gall.—On margin of leaf; sometimes on mid-rib. 
Mannert of growth.—Sessile, solitary, glabrous, glossy. 
Colours.—Green, striped with pink or red, yellowish, brown. 
Average dimensions of a mature specimen. — Height, 
4mm.; breadth, 3 mm.; girth, 9 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 the 
same or the following month. 
Parasite, No. 66. 
Cameron says: “Neither as regards the gall, or 
insect, is this to be known from A. 4-//neatus. I have 
no doubt that it is only A. quadvilineatus, the galls of 
which occur on the leaves” (‘ Brit. Phyto. Hymen..,’ 
vol. iv, p. 96). Mayr remarks that they so greatly 
resemble each other as to be indistinguishable. 
In form this gall is irregular; it may be conical, 
oval, or roundish, more or less deeply ribbed ‘longi- 
tudinally, and when on leaves larger than when on 
catkins. 
The larval chamber is large with thin walls. 
