48 THE PHRYGANID.E. 



necessarily confined to the bottom for their food, 

 and that, no doubt, is the particular place at 

 which it can be found the different species being 

 of course led by instinct to select the proper and 

 peculiar materials for their habitations. " Pro- 

 fessor Rennie," says a writer in the Saturday 

 Magazine, "made repeated experiments with the 

 larvae of the phryganidae, in order to ascertain 

 their mode of building. He deprived them of 

 their coverings, and furnished them with materials 

 for constructing new ones. He found that they 

 worked at first in a very clumsy manner attach- 

 ing with threads of silk a great number of chips 

 to whatever materials were within their reach, 

 and thus surrounding themselves with materials, 

 many of which are never used in the perfect 

 building. Unskilful as their efforts may at first 

 appear, there is much wisdom in this aggregation 

 of all the substances within their reach before 

 their dwelling is actually commenced ; for when 

 these preparations are completed, they are able to 

 devote their whole attention to. the building, and 

 to select the requisite materials from the heap 

 close at hand." 



The larvae feed principally on tender aquatic 

 plants, but some species are carnivorous preying 

 on smaller insects, even of their own kind. Taken 



