38 



THE AQUARIUM, 



who spends a great part of his time in making Httle 

 bricks, which he builds up round him until they form a 



Fig. 25. 



DiatojHS. 



Fig. 26. Fig. 27. 



circular tube, sticking out from the stem or leaf of a 

 water-weed. Then there are the Vorticellae or Bell- 

 animalcules shown in 

 Fig. 29. They are like 

 Lilliputan wine-glasses 

 set on ridiculously long 

 flexible footstalks, which 

 have a habit of suddenly 

 coiling up, cork-screw 

 shape, bringing the bell 

 to the base from which 

 the colony springs. We 

 may have Stentor, and 

 Vaginicola, and of larger 

 forms the interesting 

 Hydra and the Fresh- 

 water Sponge. In fact, 

 there is an almost end- 

 less variety of forms, 

 both of animal and plant life, to reward the diligent 

 microscopist. 



A capital tank for microscopic organisms may be 

 constructed out of a biscuit-tin (full size). From the 

 back and front of this box a large piece of tin should be 



Fig. 28. 

 Char a. 



Fig. 29. 



Vorticellcr. 



