Parasites and Predators 



are interesting. Their subterfuges to gain their ends, the 

 inordinate periods over which many of them can exist 

 without food and the fact that many of them can only 

 attain maturity after having parasitised two hosts, all 

 combine to make their lives worthy of careful study. The 

 insect parasite, be it said, does not scatter its favours at 

 haphazard ; it is every whit as careful to lay its eggs on 

 food which will suit its young as the moth, which deposits 

 its eggs on a certain food plant ; it takes infinite care that 

 the food may be in a fit condition for consumption when 

 its larvae are ready to make use of it. 



Few insects show better judgment in finding where 

 to lay their eggs than a little black wasp which seeks 

 out the common museum-beetle. These museum-beetles 

 belong to a large family known as the leather-beetles, 

 from their partiality for such fare. All of them are drab 

 little beasts and our example is a voracious devourer of 

 feathers, dried insects and the like. The grubs of these 

 beetles are peculiar amongst beetle larvae in being hairy, 

 exceptionally so, a fact which serves as an excellent 

 protection from most of their enemies, for few creatures 

 will attack a hairy insect. Our little black wasp is not to 

 be put off by such a trifle as a fur coat ; she hunts 

 assiduously for the beetle grubs amongst the feathers and 

 similar substances which they frequent. Having found a 

 victim, the delicately fashioned little wasp jumps upon 

 his back. Such a proceeding is more than the beetle grub 

 can stand, and he struggles violently to rid himself of his 

 uninvited guest. The more he struggles, however, the 

 tighter the wasp clings, till at length, tired out by his 

 efforts, his violence subsides. This is the chance for 

 which the little wasp has been waiting ; she curls her long, 

 flexible body round to the under side of the grub and 

 inserts her sting just behind its middle pair of legs. 



The usual effect of this proceeding is to paralyse the 

 grub, but on this point the wasp is most careful to make 

 every investigation. To watch her testing her victim to 



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