306 CLASS VI II. 



Metamorphosis complete. Mandibles two, forficate, narrow, sub- 

 arcuate. Palps two biarticulate, very distant, inserted under the head. 

 (Larvse and Pupae living parasitically in different Hymenoptera.} 



This order, first distinguished by KIEBY, cannot well be united 

 with one of the others, and least of all with that of the Hemi- 

 pterous Insects, as some would desire. The natural affinity is 

 difficult to determine ; perhaps this order stands between the 

 Orthoptera, Neuroptera, and Hymenoptera. In this uncertainty 

 respecting the true place, we think we have some grounds for our 

 choice, to place it after the flea, in the perfect metamorphosis as 

 well as in the presence of four rudiments of wings in the genus 

 Pulex. However small, moreover, the number of insects of this 

 order may be, that can afford no sufficient reason either in an 

 artificial or in a natural system for rejecting it. 



The winged individuals, on which the characters of the order 

 are founded, are, as BTJRMEISTER had sagaciously 'surmised, and the 

 complete investigations of the excellent C. TH. VON SIEBOLD have 

 demonstrated, all males. In these, two large compound eyes are 

 present, which consist of few faettes, separated from each other 

 by a raised margin. Simple eyes are wanting; the antennae are 

 composed of few joints, ordinarily split at the extremity into twc 

 parts, or as if branched with lappet-like appendages. In front oi 

 the wings are two small convoluted parts, named by KIRBY Elytra, 

 but which do not cover the wings. It was formerly thought thai 

 they were attached to the first ring of the thorax, and in that case 

 they could not in any sense be looked on as imperfect wings oi 

 elytra; but more accurate investigation has proved that they belong 

 to the metathorax, and, therefore, may keep the name given tc 

 them by KIRBY. They recal the short elytra of some Phasmatidce 

 The middle piece of the thorax is prolonged into a shield over the 

 abdomen. The tarsi have mostly four joints, in other species three 

 or two, and no claws at the extremity. The wings (hind wings] 

 are large, thin, whitish, opaque, and have some nervures wind 

 radiate towards the circumference. The oral organs are somewhat 

 differently described by SAVIGNY, whilst he regards as maxillce the 

 parts described by KIRBY as palpi 1 . The under lip has no palpi, 

 (WESTWOOD considers the palpi as belonging to the under lip, and 



1 SAVIGNY'S communications to LEACH were published by tbe latter in bis Zoologi- 

 cal Miscellany, TIT. i8r7, p. 13$. 



