Our British Snails 19 



of rivers. Here we are introduced to the great 

 bivalve family which is unknown on land, and 

 our trophies range from the freshwater mussels, 

 as large as our hand, to others hardly larger than 

 a pin's head. These must be sought at the 

 bottom ; but on the weeds, or on the bottom, will 

 be found not a few species of gasteropods or 

 univalves, some of which we may have noticed 

 in a freshwater aquarium. These, of course, are 

 closely connected with the land shells, which 

 the bivalves are not. They can be brought home 

 alive in a tin box with a little moss, whereas 

 for the land shells a calico bag with a little foliage 

 therein is best. In both cases some small glass 

 tubes with corks should be brought in a tin box- 

 in order to keep safely and separately the tinier 

 kinds. You can often discover what small shells 

 inhabit a particular ditch or pond by noticing 

 the cases of caddis-worms, some of which are 

 formed almost entirely of shells instead of vege- 

 table fragments. 



Using the precious gift of observation, we have 

 found our shells ; at home we exercise the other 

 gifts of comparison and order, in the preparation 

 and arrangement of our collection. A dash 

 of quite boiling water kills instantaneously any 

 molluscs w-hose shells we want to preserve, 

 and then the body is extracted after the fashion 

 observed with regard to winkles at tea. Be 

 careful to get out all the body of the animal, and 



