134 The Microscope. 



to draw itself in ; but it would immediately recom 

 mence the beautiful process of expansion. 



I lost sight of this floscule from the partial drying 

 up of the drop of water which contained it. The 

 specimen of Melicerta ringens occurred, precisely as 

 was to be expected, on a stalk of duckweed. This 

 is the wonderful animalcule which actually builds a 

 house for itself of globular pellets laid neatly together. 

 Mr. Gosse watched an animal of this species while in 

 the act of building its tube, and has described what 

 he witnessed, in the " Transactions of the Micro- 

 scopical Society," vol. iii., 1863. It makes the separate 

 bricks of its edifice from the solid particles in the sur- 

 rounding water, collected by means of its wheel-appa- 

 ratus, and probably cemented by a glutinous substance 

 of its own producing. 



The melicerta, like the floscule, often indulges its 

 shyness by retiring deep into its tube, and into its 

 self ; but if the dark tube is watched for a while, we 

 become aware of some sort of commotion at its mouth ; 

 then some feelers look out, and next a thick shapeless 

 lump, as if of flesh, appears, and then quickly enough 

 the four leaf-like expansions are turned out with a 

 deal of force, their cilia revolving at a great rate. A 

 knock on the table or microscope makes it retire, just 

 as is the case with the floscule. The melicerta tubes 

 are visible to the naked eye, and, being opaque and 

 dark, are very easily kept in sight. I placed mine 

 in a small quantity of water, guarding this as best I 

 might from evaporation, when called for a few days 

 from home, but on my return the tube proved to have 



