THE CIIALCIDITES. ] 87 



the Cryptogastri, in which the external integument of 

 the abdomen is not usually separated into distinct 

 segments, but consists of one entire piece. 3d, the 

 Areolarii, which have a small second submarginal cell, 

 and in the typical genus the mouth is produced into a 

 proboscis ; and, lastly, the Cyclostomi, in which the 

 clypeus has a deep excision, which, when the mandibles 

 are closed, give it the appearance of a circular cavity. 

 The Exodontees we have above sufficiently characterised. 

 They form a very small assemblage of genera, but 

 amongst which Chasmodon is remarkable for being ap- 

 terous, and Alysia is the type. Throughout both these 

 large divisions of the Ichneumonides, the normal and 

 abnormal, we are acquainted with very many exotic 

 forms which have not yet been characterised. It is, 

 doubtlessly, contiguous to these groups that the eccentric 

 and extraordinary family Evaniada, comprising within 

 it Aulacus and Fcenus, are to be inserted. Somewhere 

 in this vicinity, also, those anomalous forms, Stephanus 

 and Pelecinus, must, of course, come ; and in a proxi- 

 mate situation to the Adsciti must, we expect, be the 

 place for Trigonalis, of which a second form has comae 

 under our notice. But time and subsequent discoveries 

 will determine these points. 



(l6l.) We now enter upon the large group of CHAL- 

 CIDITES, which, in the majority, are minute insects. They 

 comprise an enormous host, the most of which are 

 splendid little creatures gaudily arrayed in the most 

 brilliant metallic colours. It is in this country chiefly 

 that attention has been paid to them, and we must be 

 grateful to Mr. Walker for his elaborate investigation of 

 the tribe. The more typical forms are the least me- 

 tallic, and are distinguished by their enlarged and elon- 

 gated posterior femora. Leucospis is singular for the 

 recurving of its ovipositor over the abdomen, and from 

 resembing the Vespida in the superior wings being lon- 

 gitudinally folded. The group exhibits, besides, many 

 peculiarities not the least of which is the reduced 

 number of the joints of the tarsi in the Eulophi ; and 



