THE MICROSCOPE. 181 



out in the slide before us, and connected with essential and most 

 important differences in the subjacent structures. 



Palate of Testacella Haliotidea (PI. XVIII.).— I do not 



know this creature, but think I remember to have seen that it is 

 carnivorous ; certainly the teeth are most formidable weapons, and 

 would be admirably calculated for cutting through tough substan- 

 ces. The resemblance borne by each individual tooth to the 

 " coulter " of a plough, as remarked by the owner of this slide, 

 seems to me interesting and worthy of notice. 



Snipe-Fly, Empis tesselata.— The passing round of slides of 

 typical specimens will, it appears to me, be one of the very best 

 aids we can adopt towards our mutual improvement. Viewed 

 from this point of view, I regard the present slide as a valuable 

 one. Although objecting on principle to the crushing flat of 

 insects, there is still much to be learnt by the careful study of 

 such a specimen. I find that such are excessively popular with 

 those to whom the microscope and its revelations are not familiar, 

 but as students advance in knowledge they come to be regarded 

 with proportionately less favour. 



Hemipteron? (PI. XX., Figs. 3 — 6).— I incline to think this 

 is a mature insect, a female with the luings undeveloped ; we obtain 

 a partial view of a very fine ovipositor-saw which seems to say so. 

 On this it may be interesting to quote for those who have not the 

 opportunity of referring, the following remarks by "Westwood : — 

 " A peculiarity occurs in some of these insects whereof analagous 

 instances have already been noticed among the Orthoptera, 

 Hotnoptera^ Aphidiv, and even in a species of Chalcididce^ namely, 

 the undeveloped state of some specimens in the imago state which 

 are nevertheless as capable of reproduction as others of the same 

 species which have acquired fully-developed wings. Thus the 

 bed-bug has never been observed but with the minute rudimental 

 upper wings, somewhat resembling the ordinary wing-case of 

 jjupte; others, again, as the species of Gcrris, Hydrometra, and 

 Veiia, are mosdy found perfectly apterous, whilst occasionally they 

 are found with full-sized wings. The winged males of Capsus 

 ambidans are stated by Fallen to be always found coupled with 

 apterous females. Chorosoma inirifo?-»iis, Prostcmvia guttata, 

 Pachymerus brevipennis, etc., are generally found with very short 

 wing-covers, but occasionally with full-sized wings." — (Introduction, 

 Vol. II., p. 454). 



This has a considerable general resemblance to the bed-bug; 

 does the mounter remember exactly hoia and upon what he caught 

 it ? Many are very local, as he will find by referring to Douglass 

 and Scott's monograph of the order (Ray Society's Vol., Introduc- 

 tion, p. 6). The best way on finding another specimen would be 



