202 BEES OF GREAT BRITAIN. 



on the bee, which has been found in its cells feeding on the 

 pupae. Having obtained a large supply of larvae of the bee, and 

 also of Monodontomerus and Melittobia, ample means of observa- 

 tion were afforded, the result of which appeared to show that 

 Monodontomerus is the true parasite of Anthophora, and Melit- 

 tobia a parasite of both genera. Melittobia attacks indiscrimi- 

 nately the larvae of both insects, but in their natural situation I 

 only found them feeding on Monodontomerus. Several cells were 

 obtained containing larvae of Melittobia, but their victim was con- 

 sumed ; therefore it was not possible to determine satisfactorily 

 whether they had fed upon the Chalcis or the bee. M. Audouin 

 discovered Melittobia Acasta in the nests of Osmia, Anthophora 

 and Odynerus ; probably there are several species closely allied ; 

 for with insects so minute, and belonging to a family in which a 

 very general resemblance obtains, it requires a practised eye, as 

 well as a careful microscopic investigation, before the specific 

 differences can be detected. The mode of attack which these 

 parasites practise appears to be made by several females obtain- 

 ing entrance to the cell of the bee and attacking its larvae, upon 

 which they deposit their eggs, to the number of one hundred 

 at least, which soon hatch, and the young larvae attach them- 

 selves to their victim, continuing to feed until full-grown, when 

 they fall off and lie inactive at the bottom of the cell ; by the 

 time the whole brood is full-fed, the larva of the bee is entirely 

 consumed. The bees and the parasites appear in their perfect 

 condition about the same time in the season, some having passed 

 the winter months in the larva state, others in their perfect 

 condition. 



Two bees are parasites upon the genus Anthophora Melecta 

 luctuosa and M. armata, the former upon A. retusa, and the 

 latter upon A. acervorum : the latter makes its appearance very 

 early in the spring, as soon, in fact, as the first wild-flowers 

 bloom ; it may be sometimes observed early in March, attracted 

 by the garden Crocus ; it continues to be found as late as July, 

 and was captured in the Isle of Wight on the 15th of that 

 month. The latter circumstance is explained by an investiga- 

 tion of a large colony in the month of November, when a large 

 portion of the brood will be found to have arrived at its per- 

 fect condition, the rest being still in the larva or the pupa state, 

 the latter fast advancing to maturity ; the entire brood of the 

 colony will pass the ensuing winter either as larvae or perfect 

 insects ; none can withstand its rigour in the intermediate 

 or pupa state. Those which remain larvae until the return of 

 spring advance to the perfect state very irregularly ; many will 

 not become perfect until May, and a few probably not until June; 

 this will account for the species being found during so many 



