62 



of a species of Ht/lvtonw, one of the Tenthredinidce or sa^sliies, which, being of 

 a bright green colour, are conspicuous to view on opening the cavity. The wasp's 

 sting is not sufficiently pungent to penetrate the human skin, but is yet strong 

 enough to puncture the integument of the larva, which is wounded, though not 

 unto death. 



Poisoned by the sting it becomes torpid, however, and lies quietly inhumed 

 in the tomb-lOte cell ready to become food for the larva of the wasp as soon as 

 this latter shall be hatched, which, from our observation, must occur in a few 

 days in such warm and genial weather as the present month has afforded. I 

 understand that in unfavourable seasons the hatching may be much retarded or 

 even not take place at all, in which case the stored up larvae and their destined 

 devourers decay in the eirth together. The wasp maggot is of a pale straw 

 colour, deepening to yellow as it grows ; it rapidly attains its full size, feeding on 

 BO amply stored a larder. It consumes the sawfly larvse one by one, leaving 

 nothing of them but their horny heads. The instinct of the wasp teaches her to 

 store the cell with none but vegetable feeders, from whose assaults her own 

 offspring are thus secure. Having completed her office of purveyor, which she 

 does by carrying in the green maggots between her mandibles, she closes the 

 cell with a thin layer of prepared mortar and immediately repeats the process, 

 till in succession, as many cells have been furnished as the length of the 

 burrow permits of her making. Where the quantity and the nature of the soil 

 are favourable she sometimes branches off in different directions, but she con- 

 trives so to mine her apijroaches as to avoid encroaching on the limits of her 

 neighbour workers. Sometimes we have found a number of ceUs filled with 

 their usual contents in close proximity one to the other, although evidently 

 traceable to distinct burrows. Having filled all the ceUs of her burrow she 

 closes the orifice. And here comes in one at least of the uses to which she applies 

 the outworks, for she detaches as many pellets from the mouth of the tube as 

 will suffice to plaster iip the cavity to within one or two lines of the surface, 

 making fiesh burrows elsewhere if required to exhaust her stock of eggs. Her 

 labour is now done — she has accomplished the ultimate task of her life by pro- 

 viding as best she may for her progeny, and soon after she dies. 



Meanwhile and during the performance of the busy operations I have just 

 been describing, we shall see in part the most marvellous passage in this insect 

 history. Not only shall we, if we take our post in front of the burrows, see 

 the wasps building their cells and carrying within their still living prey, but 

 flitting about in the sunshine smaller insects will appear, now settling for a 

 moment or riinning with restless speed here and there, but, ever and anon one 

 of them will enter one of the burrows ; sometimes to be immediately expelled, 

 if the wasp happen to meet her in the passage, not seldom remaining in for a 

 minute or two. These are the parasites, who, like the cuckoos amongst birds, 

 come to take unfair advantage of the labours of the wasps. Their bee-like shape 

 will strike the o]jseiver, but they are not true bees, although belonging to a 



