3S0 L September, 



ON SCOLOPOSTETRUS ABJUNCTUS, D. & S. 

 BY JAMES EDWARDS, F.E.S. 



Having had the good fortune to meet with a male example of this 

 species, as defined at p. 279 ante, I wish to point out some additional 

 differences, beyond the presence or absence of tubercles, in the 

 structure of its mesosternum as compared with S. affinis. In the 

 former the mesosternum has a distinct longitudinal channel before the 

 middle coxae, and the comparatively smooth round space on each side 

 is dull by reason of its exceedingly fine sculpture, while, in the latter, 

 the mesosternum has a smooth, shining, impunctate space on each side, 

 and there is no channel before the middle coxse. The specimen in 

 question has been submitted to Mr. Saunders, who admits that it 

 possesses the characters which I assign to the species. 



I should like to take this opportunity to make a few remarks on 

 Mr. Saunders' notes on my paper on this genus. 



I have shown that we have, in Britain, six kinds of Scolopostethus, 

 and until it has been shown that in an average gathering of these 

 insects the exceptions to the characters laid down in my table amount 

 to something more than an occasional aberration, I think that such 

 characters may reasonably be regarded as good. In the absence of 

 proof to the contrary, I am content to treat our six kinds of Scolopos- 

 tethus as distinct species. The whole question does not seem to me to 

 be one of wisdom or otherwise, but simply whether the characters 

 employed in my table are sufficient for the separation of the several 

 kinds of Scolopostethus which occur in this country, and whether I have 

 included any which do not occur here. 



As Mr. Saunders did not examine the apical lobe of the style of 

 S. punctatus under similar conditions to myself, he is, I take it, scarcely 

 in a position to criticize either my figure or my statement that under 

 a one-third objective the surface of the terminal lobe is apparently 

 perfectly simple. Most natural objects, possessed of the three 

 dimensions of length, breadth and thickness, present a different form 

 under the least change of aspect, but I think that the differences shown 

 in my figures can scarcely be more due to difference of aspect than of 

 form, for the following reasons. The styles figured are mounted on 

 card as nearly in the same relative position as the differences in their 

 contour will admit, they were all drawn at the same sitting, by the 

 same means, and under the same amplification, viz., a one-third objec- 

 tive, which I found to be the highest power that would give a view of 

 the entire style at one time. 



