250 THE ENTOMOLOGIST. 



sessiliflora or Q. pedunculati-t, as no other oak occurs near 

 Zwickau), and stands next to the gall of Spathegaster 

 Jiosculi, Gir. (= Giraudi, Tschek.), in form, structure, and 

 pubescence. It occurs on the midrib or on a side rib, is fusi- 

 form, 3'5 to 5"3 uiilliraelres long by 2 to 2'4 millimetres broad, 

 and is abruptly and bluntly conical at its extremities ; it is 

 greenish yellow, partially rosy, and is said to be blue-green 

 in its young state ; it is thickly covered with soft, pustular 

 hairs, which become depressed when the gall is dried; it is 

 thin-walled, and encloses a large larva-cell without an inner 

 gall. According to Von Schlechtendal the fly appears in the 

 second fortnight of May. It is very probable that S. verru- 

 cosa and jS. Jlosculi are the same species, as, apart from the 

 galls being so similar, 1 am unable to differentiate the flies. — 

 G. L. Mayr. 



This is not known as a British species. — E. A. Fitch. 



74. Spathegaster vesicatrix, Schlechtendal. — According 

 to three typical examples now before me, this gall, which to 

 judge from the specimens of the leaves occurs on Quercus 

 sessUijiora or Q. pedwiculata, appears as a circular swelling 

 of the leaf, measuring from 2 lo 3 millimetres in its horizontal 

 diameter, so thai the epidermis of the upper side is separated 

 from that of the under side by about r3 millimetre; the 

 green or whitish surface of the ujjper side has in its centre a 

 little conical projection, from which small ribs radiate to the 

 margin of the gall ; the smface of the under side is without 

 the papilla, and it is not so regularly ribbed. The larva lives 

 between these two moderately convex surfaces, without being 

 enclosed in an inner gall. One old gall, which is embedded 

 in a brown leaf, is of a brownish yellow colour, has a much 

 harder upper surface, is not transparent, nor does it show- 

 any signs of being ribbed ; the similarly-coloured under side is 

 quite flat. Since the description of this gall appeared in the 

 ' Stettiner entouiologische Zeitung,' 1870, p. 397, Herr von 

 Schlechtendal has bred the- fly, of which 1 have two speci- 

 mens, at the beginning of June. A similar, though decidedly 

 different, blister-gall 1 have found on Q. pubesccHS, as well as 

 a second on Q. cerris, but have obtained the producer from 

 neither. — G. L. Mayk. 



Miss E. A. Ormerod has written me as follows respecting 

 lliis species : — " I found galls of lliis species first on Quercus 



