the Wasp and Rhipiphorus paradoxus. 205 
specimens I did not fully appreciate the difference between 
them and the wasp-larve, the spirits in which they were 
preserved having destroyed much of their character. To ap- 
preciate the difference between them and the wasp-larve— 
in faet, to make their acquaintance thoroughly, one must see 
them alive and in all their degrees of development. 
Mr. Stone's description, too, which is the only published 
one we have, does not at all enable one to distinguish them, 
his most prominent characters being two, which are shared by 
the wasps themselves—namely, a transparent dark line down 
the back, and the contents of the body seen through the skin 
looking like curds. It is true that these characters are more 
marked in the Rhipiphorus than in the wasp; but as they 
vary much in degree in the latter, no description, taking them 
for characters, could ever enable one who has not himself 
seen them to be sure whether his wasp-grubs were Rhipiphori 
or not.. There are, however, good and sufficiently recog- 
nizable characters by which to know them; and to enable the 
reader to do so I append a full description, with figures, which 
will supply this lacuna in entomological knowledge 
The opportunities I have had this year háve made me 
thoroughly familiar with them; and the first fact which I 
that Rhipiphorus-larve are never to be seen in open cells. 
All our proposed plans for feeding and watching them have 
preserved in spirits to show as a pièce justificative, it is neces- 
sary in dealing with these insects to proceed with extra caution, 
