316 THE RIVER-SIDE NATURALIST. 



pair being the longer, and often with the greater number 

 of joints. The antennae setaceous ; wings with simple 

 neuration and but few transverse nervules ; ordinarily 

 covered with hairs, which sometimes simulate scales. 

 Larvae (known as Caddis-Worms) with well-developed 

 thoracic legs and anal crotchets, but without prolegs, living 

 in tubes covered with extraneous materials ; pupa lying 

 free in the case, or occasionally in a special cocoon ; only 

 active just before its metamorphosis ; habits, with one or 

 two exceptions, aquatic." 



This order is divided into seven families, distinguished 

 chiefly according to the structure of the maxillary palpi 

 the Phryganidce, Lymnophilidce, Sericostomidce, Leptoceridce, 

 Hydropssychidce, Rhyacophilidce, and Hydrophilidce ; of which 

 the first, the Phryganidce, is what we have chiefly to do 

 with. In the two latter the larvae inhabit fixed cases ; 

 in the others the cases are free, and carried about by the 

 inmates. 



The Phryganidce are generally found in the neighbour- 



DIFFERENT FORMS OF CADDIS CASES WITH THE SILK GRATING. 



hood of water. The larvae live upon aquatic insects and 

 leaves of water-plants, and reside in the water in cases 

 made up of all kinds of substances shells, bits of stick, 

 sand, &c. which the insect collects as a house to live in 

 before taking on the pupa state. Westwood, in describing 



from one to six articulations. It is attached close to the base of the 

 outer lobe of each maxilla. 



