LABV^ OF WATEE-PLIES. 



243 



Fig. 152. Phryganea grandis. 



species, nor is it necessary, for reference to a few of them 

 will be quite sufficient to remind those who do know, or to 

 show those who do not know, how very interesting the lai-vse 

 of the Caddis-flies are. 



The worm of Phryganea grandis makes a cylindrical case 

 (a. Fig. 151) of almost equal diameter throughout, and forms 

 it of portions of leaves ajid other vegetable matter arranged 

 spii-ally. This larva and its case are generally found in ponds 

 or very slow-running streams. The insect, in common with 

 many others, has the habit of turning itself while within its 

 tube, so that it can protrude its head at either end. Phryganea 

 grandis (Kg. 152), about the 

 largest British species, is a 

 little more than Jin. long, 

 and its wings, when expanded, 

 are at least 2in. from tip to 

 tip. It is one of the com- 

 monest and handsomest of 

 the Caddis-flies. It may be 

 known by its ash-coloui-ed 



anterior wings, brown posterior wings, and yellow-ringed 

 antennsB. Like aU its relatives, it folds its wings alongside 

 of its body when at rest. 



The larvae of P. obsoleta, P. striata, and all of the family, 



make the same kiad of cases as that of P. grandis. P. minor 



is the smallest member of the Phryganeidse. It is rather a 



handsome insect. Its anterior wings 



are spotted. 



The larvae of the large and well- 

 known family of the Limnophilidie 

 make cases very varied in their con- 

 struction. They may be found either 

 ^'"earva ^LiMNOPHilus i^ stagnant or quick-running water. 

 RHOMBiccs. The case of the lAmnophilus rhombicus 



(Fig. 153) is rather common and cum- 

 bersome. It is made of pieces of vegetable fibre, pieces 

 of stick or twigs of various thickness, bits of grass, and 

 portions of moss. These are all cut about the same length 



B 2 



