862 MANUAL OF MODERN FARRIERY. 



the longest of this kind of larvse, and generally inhabits a 

 case formed of two pieces of reed or rush, which at its full 

 growth it fixes to some water-plant, and drawing it oflP, it 

 appears in the larva condition, as represented plate xv. 

 fig. 19. It inhabits the streams of northern Wales, but 

 always those whose bottoms consist of limestone or large 

 pebbles. It is straight and rough, from being covered with 

 sand or gravel, and has the appearance of a small stick 

 of which the pith was decayed before the insect, in its state 

 immediately succeeding its exclusion from the egg, lodged 

 itself. Advanced to a larva state, which is generally 

 in April or the beginning of May, it leaves its case and lath 

 covering, a sort of skin resembling a fish's bladder, (which is 

 the way with the whole genus,) becomes transformed into 

 its perfect condition, with four wings, and paddles upon the 

 top of the water, from which it seldom rises to fly : in this 

 state it is well known in England and Scotland by the 

 name of the stone-fly, and in Wales is denominated the 

 water-cricket. 



There are several kinds of cadews, which in their maggot 

 or larva state house themselves — one kind in straws, and 

 called in consequence straw-worms, already referred to ; 

 others in two or more parallel sticks, creeping at the bottom 

 of brooks ; a third, in a small bundle of pieces of rushes, 

 duck-weed, &c. glued together, wherewith they float on 

 the surface, and can row themselves about the water with 

 the help of their feet : both these are called cad-bait. It is 

 a curious faculty that these creatures possess of gathering 

 such bodies as are fitted for their purpose, and then gluing 

 them together, some to be heavier than the water, that the 

 animal may remain at bottom where its food is, and others to 

 be so buoyant as to float, and there collect their sustenance. 

 These coverings are coarse, and show no outward art ; but are 



