296 THE DRY-FLY MAN'S HANDBOOK 



" The larvae of various species of Chironomus are 

 popularly called 'blood-worms' owing to their colour. 

 They frequent muddy ditches, sluggish rivers, lakes, 

 and ponds. Very often they may be seen in water- 

 butts or wooden cattle-troughs. Their food consists 

 of dead leaves or other vegetable refuse, and when 

 the mud is of sufficient depth they make therein a 

 shelter in the form of a nearly vertical tube, with 

 the mouth opening out on to the surface. Miall, in 

 his work on this genus, states that ' If a larva be 

 placed in a saucer with a few bits of dead leaves 

 it will gather them about its body, weaving them 

 together with viscid threads passed out from its 

 mouth. In a quarter of an hour it will be com- 

 pletely concealed by a rude sheath, which is not 

 easily distinguished from the similar objects which lie 

 around." 



" In course of time the blood-worm undergoes a 

 metamorphosis, becoming a pupa. The head-end 

 becomes much enlarged, and the swathed wings, 

 limbs, and antennae of the perfect insect show through 

 the thin skin. Two feathery branchiae project beyond 

 the head, enabling the pupa to maintain its supply 

 of oxygen as it lies at the bottom of the water with 

 its tail buried in the mud and its head just projecting 

 above the surface. In due course this pupa comes 

 up to the top of the water by means of a series 

 of jerks, splits open its skin, and the perfect fly 

 emerges." 



" The female insect, after impregnation, expresses 



