THE A DAPTA TIONS OF AQOA TIC INSECTS. 7;« 



and powerful flying dragon flies, at the same time being supple and l.ght for 

 the capture of such delicate insects as May and Caddis flies and gnats All 

 insect, canght are better killed in the usual lethal chamber of Entomologists- 

 the "kilhng bottle." Laige dragon flies can be first disabled by a sharp 

 quK-k pmch on the thorax. Great care must be exercised in the manipulation 

 of delicate species of Ephemera, Trichoptera, and Culicid^n. The Ephemera are 

 delicate insects and well nigh impossible to preserve with any satisfaction in 

 a dry state owing to their bodies shrinking after death so as to render identifica- 

 tion impossible. One at least out of every species caught should be preserved 

 m spmt. Cvlicidc, can either be preserved in a dry state or as microscopic 

 specimens. Beetles and aquatic bugs can be preserved in a dry state, ar d their 

 legs, antennae, etc., set so as to allow an easy examination of these parts This 

 also applies to the dragon flies and the more robust species of Trichoptera. All 

 aquatic larvic must be preserved in spirit. 



The Caddis flies ^Trichoptera) ^ve a small order of insects of which lam 

 informed by Mr. Lefroy, Imperial Entomologist, about thirty Indian species 

 are known to entomologists, and no doubt there are many others awaitin- 

 determination by some enterprising person who will make these a special object 

 of study. Collectors have hitherto somewhat neglected this interesting order 

 The reasons no doubt being that Caddis flies when caught and " set " do not 

 form as attractive an appearance as the more showy butterflies and moths, 

 bome species are comparatively large, others again are extremely small. In 

 appearance Caddis flies resemble moths so closely that they are often mistaken 

 as such. Great difference of opinion has existed between naturalists as to the 

 true position of these insects. They have been included with the Hemiptera 

 and Lep^doptera. but now it is generally agreed that they form a separate group. 

 The mam distinguishing feature of the order is the wings which are covered 

 with small hairs. (Greek rp,?o. hair, and ..,. wing.) Caddis flies are seen 

 more generally in the evening dancing lightly over the water in small groups. 

 The antenna, are long and composed of many joints. The body of a Caddis 

 larva is soft, white and utterly unprotected and therefore liable to the 

 attacks of many foes. To guard against this the larva makes itself a case of 

 stones, sand, bits of stick, dead shells, and a variety of other materials which it 

 may find in the water. Within this tube is a silken thread-like covering, or 

 rather I should say, the silken covering is spun first and the outside cover' 

 attached to this. This hollow cylinder enclosing the larva is open at both 

 ends. If a larva be drawn from its tube and examined with a lens at the 

 hinder end of the body two hooks curving inwards will be observed. These 

 serve to secure the insect firmly to its tube. The resistance these hooks offer 

 -11 be appreciated by those who have ever tried to drag a living larva fron. 

 Its case. The larva is at all times totally submerged and can therefore only 

 obtain air from the water though the exact mode of respiration has not quite 

 hrjlve n/r; P-f- ^^-^^ ^"""ng Mr. Taylor says-'- The animal is not 

 however still but at intervals waves its body up and down causing a stream of 



