76 THE ENTOMOLOGIST. 
Verh. der zool.-botan. Gesellschaft, Wien, xix. 559)—is but a _ 
synonym of one of Giraud’s own species, S. flosculi (1868, 
Ann. Soc. Ent. Fr. p. 54), as pointed out by Dr. Mayr. 
Ceroptres arator, H., occurs in the gall as an inquiline, in 
the summer of the same year.—L. A. Fitch. 
42. Spathegaster aprilinus, Gir.—This vesiculate gall, 
normally about as large as a pea, is generally developed on 
the terminal, rarely on the axillar, buds 
of Q. pubescens, but it sometimes 
occurs on those of Q. sessiliflora. It 
is remarkable on account of its rapid 
growth, as it becomes mature, and ex- 
hibits the circular hole made by the 
exit of the fly, within a few days after 
the bursting of the buds. It is spheri- 
cal, oviform, or knobby, and either of 
a yellowish white or yellowish green 
colour, partly rosy, and covered with 
short scattered hairs; at its base it 
rests on the large exterior bud-scales ; 
wie ih the interior scales, which easily fall 
Srarnecaster arriinvs., Off, are dispersed about its upper part. 
It consists of a juicy, thin-walled 
marenchyma, and contains from one to five cells, which are 
conspicuous on the outside, appearing like bumps, and are 
often distinctly divided by furrows; in the interior a some- 
what perpendicularly-placed marenchyma forms the division 
of the cells. The cells are large in comparison to the size of 
the insect, generally oviform, and for the most part placed 
upright on their longitudinal axis. The galls are often so 
small that the buds which contain them can only be recog- 
nised through the bud-scales which are less regularly placed 
and are more open. Each gall-fly, when escaping, makes a 
circular hole in the substance of the gall, but it is done in 
such a mauner that the piece cut out is left adhering at one 
point. Soon after the escape of the fly the gall shrivels up 
to such a degree that we only meet with a dry crippled bud 
in its place. Dr. Giraud states, in his ‘Signalements,’ &c., 
that he found many galls on April 20th already pierced, and 
yet he obtained a number of flies up to April 23rd. On 
the 17th of April, last year, 1 found these galls on the 
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