o/" llhipipliorus paradoxus. 195 



rapid feeding-up wliich occurs in so many Hymenoptera. I, 

 ou the otlicr hand, was as much astonished at my own obser- 

 vations on the ('hnjsidcs as j\Ir. Murray can be incredulous of 

 the facts recorded by Mr. Stone. Tiic larva of Chrysis hi- 

 dentata began to spin its cocoon in eleven days from the date 

 of the egg-hatching. Chrysis ne(jlecta took rather a shorter 

 time. But in one instance in which I reared a larva of Chrysis 

 i(jnifa, and happened to know the date on which the egg was 

 laid, 1 found, two days after that date, a " minute larva " 

 (^ inch long, about one-thirtieth of the full-grow^n larva in 

 bulk), and in four more days the larva was full-fed. 



On Mr. MuiTay's next point, as I have no fresh light to 

 throw on it, I will merely remark that, as I read the recorded 

 facts, the larvae that Mr, Stone found unemployed in eating 

 wasp-larva3 were not larvjB that had still some eating to do, 

 but were those that had, as Mr. Mun-ay expresses it, eaten up 

 their man and retired from active life ; thougli not yet pupa', 

 they were about to enter that state. All larva? take a pro- 

 longed rest at this stage of their existence. Mr. Murray, who 

 Avill not allow that a larva can feed up in two days (not from 

 the egg, but from a small size), surely does not ask us to sup- 

 pose that the larva becomes a pupa the instant it has done 

 feeding. Chrysis, wliich fed up in four days, remains before 

 its change to pupa nearly ten months. Will he not allow 

 Ehipijjhorus a day or two? 



I do not see that the question of size has much bearing upon 

 the question at issue. In the one view the large specimens 

 are large because they have eaten a queen instead of a worker 

 larva, in the other the wasps have fed them more plentifully 

 because they were in queen-cells. Still, if the capacity of 

 parasites for varying in size which Mr. Smith mentions be not 

 called in by ^Ir. Murray to account for those in the queen- 

 cells being able to assimilate a larger supply of nutriment 

 than the others, he must give us some other hypothesis. The 

 case is obviously not parallel to that of the wasps, Avhere the 

 larger insects are queens, the larger Rhipiphori differing only 

 in size. So much has this difficulty been felt, that I have 

 seen it somewhere advanced that the larger specimens are 

 always females — making the case parallel with that of the 

 wasps themselves, which Mr. MuiTay has proved not to be 

 the case. Why, if difference of feeding can produce the result, 

 Mr. Smith should be asserted to be carrying his argument to 

 the extreme in supposing that the mere difference between 

 eating a worker-grub and a queen-grub is sufficient to account 

 for the greater dimensions of the one in the queen's cell over 

 the one in the worker's cell, 1 cannot at all understand. A 



