630 EXTERNAL ANATOMY OF INSECTS. 
and I only regret that his labours were directed to so 
small a portion of the Class Insecta, and in that portion 
only to a part of the upper wing ;—I say only a part, be- 
cause all those areolets of the posterior part of the wing, 
in some cases amounting to, five*, that lie behind his cu- 
bital cellules, are not employed by him as diagnostics, and 
are left without a name. By dividing the areolets of the 
Intermediate Area of these wings into three portions, the 
basal, medial, and apical’, I have endeavoured to re- 
medy this defect, and by naming each set of areolets in 
the middle portion, as you will see in the Orismological 
Definitions, under the term Areolets, you will find it 
easy to describe any given areolet and its place in the 
wing ; those of the base may be called the anterior, in- 
termediate, and posterior, where three occur ; and the first 
and last of these terms will suffice where there are only 
two; the apical areolets, or those that are open to the 
margin, may be called, first, second, and third in the 
order of their occurrence, reckoning from the anterior or 
costal margin. 
In this Order it is curious to trace the progress of neu- 
ration in the wings of different genera. ‘Thus in Pszlus 
only the costa} nervure and the stzgma are to be traced ¢ ; 
in Chalcis the postcostal, and stigma‘; in Proctotrupes 
(Codrus Jur.) and Leucospis the costal, postcostal, stigma, 
and a nervure representing the externo-medial and in- 
terno-medial coalescing into one °; in Omalus the basilar 
areolets appear f ; in Crabro both basilar and medial 8 ; 
a Prate X. Fie. 8. 
> Ibid. Fic. 8. basal e*, medial f*, apical g. 
¢ Jurine Hymenopt. t. v. Gen. 48. 4 Ibid. Gen. 47. 
¢ Ibid. Gen. 45, 46. Comp. Prate X. Fic. 11. 
* Jurine Jbid. Gen, 43. & Ibid, t. iv. Gen. 47. 
