446 INSECTA. 



trunk, these bodies are not true wing-cases, but parts analogous to those 

 (pterygoda) we have already observed at the base of the wings in the Lepi- 

 doptera. The wings of the Rhipiptera are large, membranous, divided by 

 longitudinal and radiating nervures, and fold longitudinally in the manner of 

 a fan. The mouth consists of four pieces, two of which, the shortest, appear 

 to be so many biarticulated palpi ; the others, inserted near the internal base 

 of the preceding ones, resemble little linear laminae, which are pointed and 

 crossed at their extremity like the mandibles of various insects ; they bear a 

 greater similitude to the lancets of the sucker of the Diptera than to true 

 mandibles. The head is also furnished with two large hemispherical, slightly 

 pediculated, and granular -eyes; two almost filiform and short antennae, 

 approximated at base on a common elevation, consisting of three joints, the 

 two first of which are very short, and the third very long, and divided down 

 to its origin into two long, compressed, lanceolate branches, laid one against 

 the other. The ocelli are wanting. The form and divisions of the trunk are 

 very simikr to those of several Cicadariae, Psyllse, and Chrysides. The 

 abdomen is almost cylindrical, consists of eight or nine segments, and is termi- 

 nated by pieces also analogous to those observed at the extremity of the above- 

 mentioned Hemiptera. 



These insects, in their larva* state, live between the abdominal scales of 

 several species of Andrenee and Wasps of the subgenus Polistes. They frisk 

 about with a simultaneous motion of the wings and halteres. Although they 

 appear to be removed in several respects from the Hymenoptera, I still think 

 it is to some of those insects, such as the Eulophi, that they are most nearly 

 allied. 



Mr. Peck has observed one of the larvae Xenos Pechii which is found on 

 wasps. It forms an oblong oval, is destitute of feet, and is annulated or 

 plaited ; the anterior extremity is dilated in the form of a head, and the 

 mouth consists of three tubercles. These larvae become nymphs in the same 

 place, and, as it appeared to me, when examining the nymphs of the Xenos 

 Rossi, another insect of the same order, within their own skin, and without 

 changing their form. 



Nature has perhaps furnished the Rhipiptera with the two false elytra of 

 which we have spoken, to enable them to disengage themselves from between 

 the abdominal scales of the insects on which they have lived. They are a 

 sort of (Estri to insects, and we shall soon find a species of Conops that 

 undergoes its metamorphosis in the abdomen of the Bombi. The Rhipiptera 

 form two genera. 



STY LOPS, Kir by. 



The first one observed and instituted by Mr. Kirby. The superior branch 

 of the last segment of the antennse is composed of three little joints. The 

 abdomen is retractile and fleshy. 



But a single species is known ; it lives on the Andrense. 



