706 



CLASS IV. LNSECTA. 



torpid. After some weeks they change into motionless pupae 

 with free limbs. Boreus is devoid of pro-legs in the larval 

 stage, and of wings -in the adult. Bittacus resembles a Daddy- 

 long-legs and has very long limbs. 



Fam. 1. Panorpidae. With the characters of the Order. Panorpa, 

 Bittacus, Boreus. 



Order 17. TRICHOPTERA.* 



Body and wings covered with fine hairs ; the latter with few 

 nervures arising from one another at very acute angles ; hind-wings 

 larger than fore-wings with a well marked anal area ; antennae, 

 thread-like ; mandibles absent. Larvae cater pillar -like ; they 

 usually construct a case to live in. Pupa like an immature 

 imago and active just before the last ecdysis. 



The Caddis- flies have their two pairs of maxillae united to 

 form a sucking tube. The meso-thorax is bulky : the large 

 coxae of the anterior legs arise close together. There are nine 

 distinct abdominal segments and the last bears a pair of pincers 



in the male. The moth- 

 like imagos are weak on 

 the wing and haunt the 

 shady margins of the 

 streams from which they 

 emerge. Mandibles , 

 though absent or obsolete 

 in the imago, are present 

 in the pupae as well as 

 the larvae. The eggs are 

 laid, in jelly-like clumps 

 of a hundred or so, in the 



The newly hatched larvae at once set about building the 

 well known caddis-worm cases, from which they protrude only 

 fthe head and thorax, a strong pair of hooks at the end of the 

 'body serving to anchor the larva in its case. The larvae breathe 

 by abdominal tracheal gills ; they live many months and in some 

 -cases through the winter ; they are largely vegetarians but 

 ut times eat other insects. During the period of pupation the 



* McLaehlaiL, Tr. Ent. Soc. London (3), v, 1865, and Monographic 

 Revision of the European Trichoptera, 1874-80. Lucas, Arch. Naturg. 

 iix, p. 285, 189S. 



. 453. Phryganea striata. 



