129 



THE LIFE HISTORY OF RHIPIPHORTJS PARADOXUS. 



BY T. ALGERNON CHAPMAN, ESQ., M.D. 



Ehipiphorus paradoxus is the only representative we have in this country 

 of the Bhipiphoridcs, a sub-family of MordcUidw, a family of Heteromerous 

 beetles. It is nearly half an inch in length. It is narrowed in front and has 

 the head bent down, so as to present some of that resemblance to a segment 

 of an orange, which is so characteristic of the Morddlida. The elytra are 

 short, pointed, and diverge from each other so as to exhibit the wings between 

 them ; in colour they are blue-black or yellow ; the legs, especially the hinder 

 ones, are long and straggling, the antennae simple, or nearly so in the female, 

 finely pectinated or rather flabellated in the male. The thorax has a curious 

 depression along its dorsal aspect, and is hollowed out on each side at its pos- 

 terior margin. The parts of the mouth are, to a certain extent, rudimentary ; 

 the mandibles are short and not toothed ; the labial palpi consist of only ono 

 joint, and the lobes of the maxilla; are rudimentary. It is said to frequent flowers 

 and to be attracted by the sap exuding from trees, but I have never seen it 

 except in its real habitat, the nest of the common wasp, Vcspa vulgaris, or of 

 Vespa rufa. That it is to be found elsewhere follows from the fact that it 

 leaves the wasps' nest as soon as it has completed its transformations. 



Shipip/iorus paradoxus has long been known to be a parasite of the wasp 

 (both of Vcspa vulgaris and of Vespa rufa), and a general idea of its habits is 

 given in an extract from the Papers of the Ashmolean Society, quoted by Mr. 

 Frederick Smith, of the British Museum. After an observation to the effect that 

 no one had hitherto observed any parasite attacking the ant, wasp, humble-bee, 

 or hive-bee, the Rev. E. Bigge, the author of the paper from which the extract 

 is made, observes, " As regards the wasp, however, it seems that this exemp- 

 tion does not exist ; for though I myself have not been so fortunate as to find 

 any specimens of ichneumon in their nests, one has been seen in them by Mr. 

 Denison in several instances, and observed in all the stages of its growth. It 

 is described by him as a fly, as large, or nearly as large, as the wasp itself ; 

 the head and fore part of the body black, the abdomen yellow, with a dark 

 streak down the back ; legs and wings black ; upper wings dusky. This fly 

 (Rhipiphorus) deposits its egg upon the grub of the wasp at the moment it 

 assumes the pupa (i.e. spins or covers itself in the cell) ; as soon as the egg is 

 hatched, it devours the grub of the wasp entirely, and itself assumes the pupa 

 and imago form in the cell of the wasp." 



