The Caddis-Worm and its Houses. 309 



where they live. Indeed, they are able to employ various 

 substances, although their capabilities for building are limited 

 to a certain extent in regard to the material and its form. 

 This was found by myself, from experiments tried with the 

 creatures themselves. Having felt extremely interested in 

 watching these caddises walking about with their differently 

 constructed houses at the bottom of the water, I felt an intense 

 desire to find out everything about them. 



It was noticed that when the caddis was turned out of its 

 case and placed in a small vessel of water containing the 

 materials with which it was wished to form another, the larva 

 would construct for itself a new house from those materials, 

 provided they were within the limits of its capabilities. 



As soon as the caddis-worms find themselves denuded of 

 their houses, they commence forthwith with the materials that 

 may be given to them, and build new ones, never stopping 

 until the greater part of their bodies are encased. 



Coloured glass, when broken up into small pieces, makes an 

 extremely pretty case. The colours may be either sorted or 

 mixed, for in either way the case is extremely pretty. With 

 broken pieces of glass the caddis builds very rapidly. In 

 fact, I generally found that cases made from that material 

 were constructed more quickly than when the worm was sup- 

 plied with other substances. Why this was so I do not know ; 

 however, glass is particularly adapted for the caddis to build 

 with. If a case of a better sort of material than glass be 

 desired, it will be found that amethyst or cairngorm will 

 answer the purpose well. But although the caddises are able 

 to construct from either of these sorts of stones, yet I used to 

 observe that when given to them the houses were always much 

 slower in their construction. 



Cornelian, agates, and onyx are all capable of being adapted 

 for cases, and look exceedingly well when finished, especially 

 if used separately. A coral house makes a very grand-looking 

 abode for a caddis, but as it is heavy, care should bo taken 

 that the pieces be selected from the most slender and thinnest 

 part of a sprig of coral. Pieces of marble broken up into 

 tiny fragments can be successfully employed by the caddis. 

 Shells, mother-of-pearl, when broken into small pieces, or 

 small shells entire, are very quickly made into suitable dwell- 

 ings by caddises. 



I have had cases made from brass shavings, and also from 

 gold and silver leaf. With the two last-named materials the 

 worms experienced considerable difficulty, for they are unable 

 to take up portions separately of gold and silver leaf, and they 

 are obliged to roll themselves up in it in an irregular way. 



