12G (June, 



On this last point Kouow goes beyond, or rather behind, previous 

 interpretations of the observed phenomena, and enquires not only 

 what nervures actually occur in a particular wing, but, to what 

 original or ideal type of neuration these nervures point. His view is 

 that the obliteration (or doubling) of an original nervure may cause a 

 family or genus to deviate from its original type, so as to deceive au 

 uninitiated observer, but that science can recover that type by pro- 

 cesses of comparison and inference — noting, e. g., not merely the 

 number of the existing nervures, but their position, and also taking 

 count of the rudiment-like vestig(is of lost nervures, and their 

 exceptional re-appearance in abnormal specimens. (Thus he has re- 

 peatedly seen specimens of Dolerus with four cubital cellules, and 

 recognises in these a reversion to the original type from which he 

 believes the neuration of normal Dolerus to have deviated. He tells 

 me also in a letter that Mr. Cameron's Taxonus gJoitinnus is really a 

 similar abnormal specimen of EmpJiytus tener. Fall., viiih. four com- 

 plete cubital cells instead of the usual three). Again, the wings of 

 most ChalcidcB and Chri/sidce are alike almost nervureless. Yet certain 

 of their genera {Leucospis and Sinicra among the ChalcidcB, Stilbum 

 and some exotic forms of Ghrysis in the other family) have retained 

 enough of the original neuration to indicate its general type ; and to 

 show that the ChalcidcB, like the Ichneumonidce, had once three cubital 

 cellules, and the Chrysidcs, like the Vespidcs, had four. By similar 

 arguments, he maintains that Aulacus and Trigonalys form a special 

 group among the Ichneumonidce, making transition to the BraconidcB, 

 while Evania, Brachygasfer and Foenus are true Braconidce, and not 

 — as Taschenberg proposed^ — to be grouped separately along with 

 Aulacus. 



For each of his three Sub-Orders Konow proposes a name formed from that of 

 some one genus belonging to it, with the suffix — idea, viz. : I. Vespoidea ; II. 



ICHNEUMONIDEA ; and III. TeNTHREDONIDEA. 



As to the first of these, ho remarks that he is inclined to see the true type of 

 the Sub-Order, not in Vespa, but in Philanthus, but he acquiesces in the common 

 usage which designates such insects popularly as '" Wasps." 



As alternative names — denoting each the one character which belongs to the 

 Sub-Order, and to that alone — he suggests : I. Monotrocha ; II. Tristega (with 

 three cellules) ; and III. Chalastogastra (with unconstricted abdomen). 

 Of these three Sub-Orders 

 I. Vespoidea will embrace all the Aculeata, and also — contrary to the views 



hitherto general — the Chrysidce. 

 II. IciiNEUMONiDEA : the IchneumonidcB , Braconidce, Cynipidce, Chalcididce, Proc- 

 totruj)idce. 

 III. Tenthredonidea : the Lydidce, SiricidcB, and Tenthredinidce. 



