41 



ON 



CADDIS-WORMS AND CADDIS-FLIES, 



BY 



R. McLACHLAN, Esq., F.R.S., F.L.S. (Vice-President.) 



21st December, 1881. 



Up to somewhat more than 20 years ago, my entomological 

 pursuits were mainly (as is often the case with beginners) devoted 

 to Lepidoptera ; but when in pursuit of moths, other insects of a 

 different order, though much like them, were often captured ; 

 these were Caddis-flies (or Trkhoptera). About that time there 

 appeared in my friend and colleague Mr. Stainton's Entomologists' 

 Annual, a series of articles by Dr. H. A. Hagen, then of Konigs- 

 berg, East Prussia (now of Cambridge, Mass., U.S.A.), on the 

 British species of these insects. Feeling probably that the 

 Lepidoptera had a full share of devotees, and scarcely offered suffi- 

 cient scope for (let me confess it) an ambitious young man, I 

 resolved to devote myself especially to Trkhoptera, and entered 

 into correspondence with Dr. Hagen, my friendship with whom 

 continues to the present day. By degrees, the whole Linntean 

 order Neuroptera (of which the Trkho2)tera form a portion, 

 according to some) attracted my attention ; but even now the 

 Caddis-flies probably receive most favour in my eyes. 



Most of us are acquainted with Caddis-worms as tempting 

 baits for fishes, and of the curious habitations constructed by 

 them, but probably only few of my audience have more than a 

 faint idea of the insects produced fi'om these Caddis-worms. 

 The five drawers before you, represent a tolerably complete 

 collection of the British species (which now number about 150). 

 I propose to briefly call your attention to some of these, with 

 passing remarks on some curious forms that do not occur in this 

 country. 



The eggs of Caddis-flies are excluded by the female in a 

 mass enveloped in a gelatinous secretion, and are usually deposited 

 on water-plants, or dropped into the water to take their chance. 

 So soon as the larvse are hatched, they commence to make houses 

 for themselves, in which they pass the rest of their aquatic 

 existence. These houses may be mainly divided into two classes. 

 Firstly, those which are portable, and only become fixed when the 



