Retrospective Criticism. 453 
Platygaster * amongst the Proctotripide of Latreille, it is singular that the 
characters of the latter family should have been completely overlooked in 
considering them to be capable of including your correspondent’s insect, 
the characters of which, as will be seen below, completely disagree with 
those of the Proctotrupide. I have therefore thought that it might prove 
serviceable to subjoin the two following tables of the char acters, Gee of the 
four very distinct families, Ichneumonide, Cynipidze, Chaleididze, and 
Proctotapides which have, nevertheless, in a greater or less degree, been 
hitherto confused with each other, and of which families many hundred 
species are inhabitants of this country. 
These tables, you will perceive, are not drawn up in that strictly scientific 
and technical form which, I am convinced, retards rather than promotes 
the increase of knowledge; neither are they intended to comprise or reject 
all those modifications in structure which the terminal objects in any group 
exhibit. The first is deduced from the manners and economy, and the 
second from the structure of the parts, of such of the insects as may be 
considered as the types of the different groups, 
TABLE 1. 
Herbivorous, forming galls upon various plants - Cyni’Pipe. 
Parasites, feeding either within or upon the surface of 
eggs, larvee, or pupe, of other insects 
Pupa naked - - - - CHaLcr’DID#. 
I am not aware of any) Procrorru‘pipe 
Pupa enclosed material difference be- (minute). 
m a cocoon tween the habits of these ( Joyxgumo/NID& 
two families = - (typical species large). 
TABLE 2. 
Antenne, not elbowed (i. e. with the basal joint short), 
and not thickened at the tips: 
Composed of more than 20 joints; ovi- 
positor with three straight fillets; wings - JCHNEUMO’NIDE, 
with numerous nerves - - 
Composed of not more than 15 joints ; ov- 
positor spiral, concealed in the abdomen; ¢ CYNI’PIDE, 
under wings with only one nervure — - 
Antenne, elbowed (with the basal joint long), and with 
the tips generally thickened : 
Under wings nerveless ; upper wings nerve- 
less, or with a few nerves; antenne 12 to 
15 jointed ; palpi long ; ovipositor tubular ; 
colours sombre - - - 
Under wings with one nerve; upper wings 
with one nerve descending into the centre 
of the wing from the middle of the front 
margin; antenne with not more than 12 > CHaLcr’DID&. 
joints ; palpi short; ovipositor composed 
of three straight fillets, generally con- 
cealed in the abdomen; colours splendid 
J. Westwood. Feb. 7. 1830. 
Leptura, Criocéride. — Sir, The communication of your correspondent 
PROCTOTRU PIDA, 
* TI observe that Mr. Stephens has done this in his Catalogue, but I am 
not aware upon what published authority. I however think the reference 
to be correct. 
