fy 428.4) 
XIX. Illustrations of specific differences in the Saws of 
@ Dolerids. By the Rev. F. D. Moricr, M.A., 
F.E.S. 
[Read October Ist, 1913.] 
Prates XXITI-XXYV. 
Havine found much pleasure and interest in the work 
of dissecting out, examining, and photographing at various 
magnifications, the terebrae of such European Dolerids as 
I have been able to procure (viz. in all thirty-six reputed 
species), | venture to offer to the Society a series of these 
photographs—the latest and so far as I can judge the least 
unsuccessful of many attempts which I have made in that 
direction, hoping that it may be of some service to any 
colleague who cares to occupy himself with the determina- 
tion and classification of that admittedly difficult group of 
Sawflies. 
The original photomicrograms here reproduced on a 
somewhat smaller scale were all taken at the same mag- 
nification (about x 240), and as far as possible under the 
same conditions as to hghting, aperture of lens, time of 
exposure, etc. Possibly by “stopping down” more I 
could have brought out better certain details of these 
rather inconveniently ‘‘ solid” (not flat) objects, but this, 
for other reasons, I was anxious to avoid. With the 
magnification employed I could only get a small portion 
of each saw into my quarter-plates; but this suffices to 
show pretty well the characters to which I propose to 
call attention, and with a lower magnification this would 
sometimes have hardly been the case. 
The late Mr. Cameron has remarked that for separating 
Dolerus spp. “the form of the ovipositor can be safely 
relied upon, but it is not always easy of application.” 
With this, as the result of prolonged study of the subject, 
I quite agree. But it seems to me that mere outlines of 
the saws, such as are given in the Plates of his well-known 
Monograph, are not really of much use to students attempt- 
ing to identify species by the characters of that organ. Such 
TRANS. ENT. SOC. LOND. 1913.—PART III. (JAN.) 
