250 THE TUBULIFERA. 



pollen, while the latter supply theirs with small in- 

 sects of various kinds. In the latter case the larva is 

 probably hatched at once, and feeds upon the insects 

 laid up for the rightful occupant of the nest, which 

 doubtless shares the same fate as soon as its presence 

 begins to be troublesome; whilst in the former the 

 egg in all likelihood lies dormant until the larva of 

 the Bee is nearly full-grown, when the parasite appro- 

 priates to his own use the whole of the nourishment 

 which his victim has been so busily assimilating. 



Besides proceeding in this covert manner, some of 

 these insects occasionally carry on their operations 

 more openly. Thus the species of Cleptes, of which 

 two are inhabitants of Britain, are said to deposit their 

 eggs in the larvse of Saw-flies, and Saint Fargeau de- 

 scribes a case in which he observed a female of one 

 of these (C. semiaurata), proceeding backwards into 

 the numerous holes formed in the ground by the 

 larvae of the Gooseberry Saw-fly, and states that the 

 following year the small space in which this operation 

 had taken place, was brilliant with the hundreds of 

 Cuckoo-flies which emerged from the burrows. 



All the insects of this tribe are to be reckoned 

 amongst the most splendid members of their class, 

 and they have been well compared with those orni- 

 thological gems of the tropics, the Humming-birds. 

 Their ordinary English names of Ruby-tails and 

 Golden Wasps also refer to the brilliancy of their tints. 

 The commonest English species, the Chrysis ignita, 

 is perhaps one of the most brilliant. It is about the 

 size of the common house-fly ; the head and thorax are 

 of a fine metallic greenish-blue colour, and the ab- 

 domen, which exhibits four small teeth in a transverse 

 row at the apex, is of a bright golden-red tint. This 



