1907. 143 



of tlic cliitin. Tlie front femora appear to fit into it, when the insect 

 draws its legs together, as it usually docs wlien captured. Hence 

 there is sometimes a diiliculty in seeing tlie cliaracter in specimens 

 not prepared witli a view to displaying it; hut, if the front legs are 

 pulled well out of tlie way, it is very noticeahle indeed, when the 

 insect is looked at upside-down. " Carding," naturally, altogether 

 conceals it. 



In all sjjecies of Tomosfetlius the wings are more or less dusky ; 

 the legs are mainly hlack in some species, in others they are more or 

 less widely yellowish. But the most important characters are those 

 which lie in the structure of the head, though unfortunately it is 

 often very diflicult to see them without special preparation of the 

 specimens. In practice one has generally to rely on neuration, size, 

 and colour-differences. 



Konow enumerates in his papers on the European Blennoeampids 

 (Vienna, 18S0) six species of Tomoslef/nis, and I possess British speci- 

 mens of all six. The following Table is founded on his ; but I add 

 certain characters which 1 have found helpful, ami explain at greater 

 length others which he states somewhat briefly, so that a beginner 

 might not realize his meaning. I have also brought the nomen- 

 clature up to date by information received from his later writings on 

 the subject, and mentioned in brackets the name given to certain 

 species in Mr. Cameron's Monograi)h. (Gnffafhinus and fmiereus do 

 not seem to be mentioned in that work either under those names or 

 others). 



SYNOPTIC TABLE OP BRITISH TOMOSTETHUS spp. 



1. 'i'eniporii without distiiicl. margin separating them from the occiput 2. 



— Tempora witli a sliarp margin separating at least tlieir lower ])art from the 



occiput. (This margin runs from near the base of the mandible [behind it] 

 upwards towards the hind corner of the vertical area) 4. 



2. Discoidal n. and 1 medial n. in fore-wing not parallel. Hind-wing with an 



enclosed medial cell. Large black species. Legs black. (Superficially 

 resembling P. atenima and It. micaiis, but a little smaller) ...nigritns, F. 



— Discoidal n. and 1 medial n. parallel 3. 



3. Hind-wing without enclosed medial cell. Legs mostly black. (Like the last sp., 



but smaller) fuUginostis, Schr. 



— Hind-wing with enclosed medial cell. Legs mostly yellow .fanereus, Kl. 



4. Tempora with margin distinct only in its lower part. Body (except the legs in 



part) entirely black gagathinus, XI. 



