66 FLY FISHING AND SPINNING 



protection against enemies. The larva uses this sheath 

 as a movable residence, and from the open end its head, 

 thorax, and legs protrude and provide the motive power, 

 the weak and maggot-like body (see Plate VII., Fig. 1), being 

 always enclosed and protected by the armour-clad case, 

 which it drags about from place to place. After various 

 enlargements to suit the growing conditions of its body, the 

 larva enters and partially closes the open end of its case ; 

 it then commences its pupal existence i.e., it becomes a 

 chrysalis, and finally, when the chrysalis stage is over, it 

 tears open the sac covering which has protected it during the 

 dormant existence. Swimming to the surface, it either 

 supports itself against some floating object or makes its 

 way to the bank. The skin then splits open and the insect 

 enters the flying stage direct (see Plate VII., Fig. 4), the pupal 

 kin being generally left in the water. 



The larva of the other family of the Caddis-fly forms 

 its home by spinning a sac, like a bag, attaching it to 

 some sheltered spot, and covering it with stones, etc. It 

 leaves this home in search of food, and when the pupal stage 

 approaches, it partially closes the aperture and undergoes 

 a pupal phase similar to the one above described, before it 

 assumes its imago existence. Some well-known forms of the 

 Trichoptera are as follows : The Red Sedge, Silver Sedge, 

 Orange Sedge, Grannom, the Welshman's Button, the 

 Cinnamon-fly, the Sand-fly, etc. In Plate VII. will be 

 seen two exquisite drawings of the larva and the pupa of 

 the Caddis-fly, by Mr. Knight. 



Fig. 1 is the larval condition of the Phryganea, one of the 

 Sedge family. 



Fig. 2 shows the larval case of this water insect. 



Fig. 3 is the pupal stage of the same water insect. 



Fig. 4 is its flying stage. 



