24 OJf THE BRITISH SPECIES OF TOMOCERUS, 



tlie yellow fading away into a leaden colour almost like that of the 

 scales. Thus, as the colour is so variaWe, it appears impossible to 

 make it o£ specific value here at any rate, and the two species 

 should be united. In fact, if naturalists describing these insects 

 would pay more attention to even minute morphological details and 

 not spend so much time in recording the position of every little 

 patch of colour, we should not be troubled with so many synonyms. 

 It appears that the common English species of Tomocerus is 

 identical with the T. triclentiferns of Tullberg; in fact in the 

 north of England at least it is very much more plentiful than 

 T. plumlea, L., of Tullb. ; while in Sweden the reverse is the 

 case, Tullberg himself not having seen tridentiferus alive when 

 he described the species. It is very easy to distinguish, as it is 

 the only species yet described with tridentate spines on the 

 spring. Lubbock indeed does not distinctly say that the spines 

 in his species are tridentate ; but he remarks that they " have 

 small processes at the sides," which amounts prettj^ much to the 

 same thing. Of the specimens I have examined there are a few 

 witli the lateral teeth so small that Lubbock's description would 

 appear more applicable, but the great majority have the spines 

 distinctly tridentate. I am not aware of any other observer 

 having previously noted this tridentate species ; and as Lubbock's 

 name is now taken up, it appears that that of Tullberg should 

 stand. Since the publication of Sir John Lubbock's monograph 

 Tullberg lias described several new species of Tomocerus, in the 

 diagnosis of which great stress is laid on the number and 

 arrangement of the caudal spines. As in the descriptions of 

 our British species this has not specially been noted, perhaps it 

 would be as well to add here a short diagnosis of each species. 



Tomocerus pltjmbea, L., of Tullberg, Sveriges Podurider, 1872, 

 =-T. longicornis, Miiller, &c. 



A.ntennEe mucli longer than the body, the 3rd and 4th segments 

 often coiled up. Spines on the dentes simple, 7-8 on each side, 

 small, and arranged in almost a straight line. Upper claw with 

 two or three teeth ; lower one acuminate, produced into a hair-like 

 point and with a minute tooth. 



Tomocerus tridentiferus, Tullb. Sveriges Podurider, 1872. 



Antennse not longer than the body. Spines on the denteg 

 tridentate, 10-11 on each side, 3 or 4 nearest the manubrium, 

 the last and either the last but two or the last but three con- 



