62 OLASSIFICATION. 



as it is very artificial, it is unnecessary to allude to it 

 further here. The Swedish entomologist, Dahlbom 

 (Prod. Hym. Sc.), arranged the Swedish species in 

 fifteen genera, namely, Cimbex, Athalia, Hylotoma, 

 Cyphona, Lophyrus, Monoctenus, Cladius, Priophorus, 

 Nematus, Tenthredo, Dineura, Emphytus, Dolerus, 

 Phyllotoma, Lyda. 



James Francis Stephens, in vol. vii of his c Illus- 

 trations of British Entomology,' described all the 

 British genera and species known by him to inhabit 

 Britain. This work, however, was by no means a 

 critical one as regards the discrimination of the species, 

 but as he gave, in most cases, the original descriptions, 

 many of which were not readily obtainable, it was, on 

 the whole, a work of some utility to the British 

 Entomologist. Stephens' classification was as fol- 

 lows : Cimbex with 8 British species, Trichiosoma 9, 

 Clavellaria 2, Zarcea 1, Abia 2, Amasis 2, Hylotoma 

 15, Schizocerus 2, Lophyrus 3, Cladius 1, Pristiphora 



9, Nematus 45, Croesus 3, Mess a 1, Fenusa 3, Athalia 



10, Selandria 40, Hemichroa 3, Sciapteryx 1, Allantus 

 47, Tenthredo 28, Dosytheus 14, Dolerus 9, EmpJiytus 

 20, Heterarthrus 1, Melicerta 1, Tarpa 2, and Lyda 21 

 species, or a total of 309 British species. 



Hartig (following Klug), in his ( Blattwespen/ dis- 

 tributed the species into thirteen " genera," and each 

 genus was again divided into sub-genera, these into 

 66 sections " and the " section " into " tribes." Each 

 division received a name, so that, on this arrangement, 

 the nomenclature of a species was rather cumbersome. 

 Thus the Tenthredo albipes of Linne became Tenthredo, 

 Allantus, Selandria, Blennocampa, Monophadnus al- 

 bipes. In fact, his * 6 genera " are equivalent to the 

 "tribes" of recent authors; and his sections and 

 tribes have become genera. He arranged the genera 

 (= tribes or sub-families) thus : Cimbex, Blastico- 

 toma, Hylotoma, Lophyrus, Cladius, Nematus, Dineura, 

 Dolerus, Emphytus, Tenthredo, Tarpa, Lyda, Xyela. 



"Westwood (Introd., ii, 113) introduced an improve- 



