60 RESULTS FROM GIPSY MOTH PARASITE LABORATORY. 



were sufficient to justify him in s[)litting the group into two distinct 

 famihes. In this move ho was hiter suijportecl by Dr. WiOiam H. 

 Ashmead. It is of course impossible to come to any definite conclu- 

 sions in a case of this kind until more has been learned concerning the 

 larval development in the other genera of the two groups, and also 

 in the related families. If it is found that this type of development 

 is characteristic of these two groups and no others, it should cer- 

 tainly be an argument of considerable weight in support of Walker's 

 views. 



RHIPIPHORUS AND OTHER COLEOPTEROUS PARASITES. 



Anyone at all familiar with the life histories of certain of the para- 

 sitic Coleoptera, Meloe, Sitaris, and more especially the hornet para- 

 site RMpiphorus, will be reminded of these genera by a perusal of the 

 preceding pages. The similarity in development, life cycle, and 

 habits even to certain minute details is so striking that one in reading 

 the excellent description of the life history of Rhipvphorus paradoxus 

 given by Dr. T. A. Chapman ^ could scarcely tell whether it belonged 

 to that insect or to Perilampus were the names omitted. A brief 

 comparison of the two may be of interest. 



So far as we know, the place of oviposition of RMpipliorus para- 

 doxus has not been observed, but other members of the family, notably 

 Myodites, oviposit commonly upon flowers of various kinds. From 

 the eggs hatch the triungulins wliich are not only analogous to the 

 planidium of Perilampus and Orasema but, except for the legs and 

 antennae, are strildngly similar in anatomical details. The dark chi- 

 tinous rings which encircle the triunguhn for protective purposes dur- 

 ing its adventurous search for its host, the backward-pointing spines 

 with which these are provided, the pair of stylets on the last segment 

 and the "comma "-shaped mandibles retracted into the buccal cavity 

 aU forcibly remind one of the planidium of Perilampus. The writer 

 is aware that the resemblance is mainly a superficial one, but it is 

 very unusual, superficial though it be. The similarity does not end 

 here, however, but is carried out even to the details of the life cycle. 

 It is more comparable to Orasema than to Perilampus inasmuch as the 

 Perilampus is a secondary while the others are primary parasites. 

 The RMpiphorus triungulin, after gaining entrance to the nest of its 

 host, conducts itself almost exactly as we have reason to suspect 

 Orasema does; that is, it enters the young host larva, emerges at the 

 time the host larva attempts to pupate, and feeds ectoparasitically 

 thereafter. It differs, however, in the fact that the Rhipipliorus tri- 

 ungulin feeds and grows to 8 or 10 times its original length wliile 

 within the host larva, while Orasema and Perilampus apparently do 



1 Annals and Magazine of Natural History, 4th series, vol. 6, pp. 314-326, 1870. 



