396 On the Parasitism o/" Rliipiphorus paradoxus. 



In one instance the larva of a wasp was found bj Mr. 

 Murray in a cell together with one of B.hifi'pliorus ^ both being- 

 stunted in growth ; in this case I am led to believe that both 

 died before the parasite was full-fed, the stunted state of the 

 wasp-grub being just what would naturally result from such a 

 catastrophe. The nest of the wasp was removed from its situa- 

 tion, and both perished in consequence ; the two larvte were 

 found head to head, that of the wasp squeezed out of shape, 

 the result, I imagine, of the dying struggles of the parasitic 

 larva. 



In cells in which RMpiphori were reared, the debris of the 

 skin of a wasp-larva was found, which Mr. Murray regards as 

 the cast skin of the larva, such, in fact, as is occasionally found 

 in the cells both of the wasp and hornet ; but I am inclined to 

 regard these skins as those of the larva upon which the RM- 

 ])ipliori had been nourished, and from which they had extracted 

 the entire contents. 



The cells which contain RhipipJiorus will always be found 

 lined and capped like those of the wasp, because, as Mr. 

 Stone has shown, the larva of the parasite does not commence 

 its attack until the wasj)-larva is full-grown and has spun 

 itself up. I have repeatedly watched the larva of wasps in the 

 act of spinning these convex caps to the cells ; and until the 

 same is observed of the parasite, I cannot but doubt the possi- 

 bility of the latter doing so. 



The following observation in Mr. Murray's paper must, I 

 think, be an inadvertency : — " I here assume, as I think is the 

 general belief, that this lining and lid are spun by the pupee." 

 I scarcely think it possible that any one can have expressed 

 such an opinion ; I at least am not aware of a single instance, 

 and conclude that for pupa we should read larva. 



There are other portions of the paper which I leave un- 

 touched ; some because I am not able to suggest any satisfac- 

 tory elucidation, and others that do not come within the scope 

 of the object I have in view, that of endeavouring to account 

 for some of the circumstances observed by Mr. Murray, and 

 also of stating that five years ago Mr. Stone convinced me of 

 the true parasitism oi Rhijnjjhorus, and I have not since ac- 

 quired any information that induces me to change my opinion. 



The following extract from the Papers of the Ashmolean 

 Society strongly supports Mr. Stone's account of the para- 

 sitism of Rhijnphorus. 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, tlie author 

 of the paper from which the extract is made, observes, '^ As 

 regards the wasp, however, it seems that this exemption does 



