June, litOO. I 121 



the winter withiu the cocoon, in order to nullify the furious onslaughts 

 when the Vesjjce are seeking to eject the remaining grubs, &c., at the 

 autumnal exodus. That they are unable to dislodge this cocoon is 

 certain, since wasp's eggs, even partially-grown larv«, have been dis- 

 covered in cells already half filled with a parasite's cocoon. 



The Cocoon is oblong, hexagonal-cylindrical, rounded at the bottom, and with 

 the operculum very flat or even slightly concave ; the longitudinal carinsB, however, 

 are only present near its apex in those specimens I have examined — which were, I 

 think always, those of the autumn brood, and not (as figured by Andre, xxxiv, 7) 

 continued throughout the cocoon's entire length. It is, nevertheless, probable that 

 the length of the carina; increase with the amount of solidity acquired, and would, 

 therefore, be more conspicuous in those of the spring brood. Rouget says when the 

 larvEE attack ? Tespce they are able to consume only three parts of the grubs, and 

 their cocoons are proportionately broader and shallower, because these cells are 

 larger. In the ordinary cells it is about 6 mm. in length and 3| mm. in diameter. 

 Stone found that each cocoon had a beautifully delicate gold-coloured lining, in 

 which the insect is enwrapped ; I cannot, however, find this in my examples, whose 

 inside is of the same dull white as the outer. The parasite emerges through a 

 clean-cut circular orifice bored in the centre of the hexagonal operculum. 



There are two emergences (at least) during the year, but it 

 appears to have been by no means satisfactorily settled, whether these 

 are distinct broods or only sexual emergences. Curtis says only part 

 of a single brood emerged in September, these being " probably 

 females," and the other part, as we are told in the Addenda, produced 

 (^ (^ at the end of the following April. " Is it not probable that they 

 (the cT (J) would have lived till the $ $ of another brood appeared 

 in the following July ?" he asks ; and on another occasion he records 

 a ^ bred at the end of May. Mr. Bignell (Ichn. of S. Devon, p. 41) 

 appears to consider the spring emergence to belong to the same 

 generation as that of the autumn, since he says, " others remain over 

 until the following May." On the other hand, Hope found the 

 imagines in August ; Wood may have been mistaken in thinking he 

 found ? ? already emerged in July (c/! Curtis) ; Andre, however, 

 says the second and more numerous brood appears in September, and 

 that the transformation to the nymph takes place before the winter. 

 If this be so, there would appear to be two distinct broods. Perhaps 

 it is sometimes single- and at others double-brooded ; in any case, 

 Curtis's theory is not tenable, I think, since in that case the S S ^^ 

 one brood would fertilize the ? ? of the next, which is contrary to 

 the laws of Nature. It is most probable that part of the brood hi- 

 bernates within the nest and part, like the majority of the Crtptides, 

 survive the winter among dead leaves, moss, and other foreign hiber- 



