18 LECTURE XII. 



One of the most elegant species of Vorticelia is 

 the Vorticelia Convallaria, a beautiful transparent 



animalcule, the body of which is formed like a bell- 



f 

 shaped flower, and is furnished with a very long 



tail or -stem, by which it affixes itself to whatever 

 substance it pleases. When a groupe of these 

 animalcules is viewed by the Microscope, it ex- 

 hibits the appearance of a set of animated flowers, 

 alternately stretching out their stems at full length, 

 and again suddenly contracting them in a spiral 

 twist as represented in the figures we are now 

 viewing. This species is very common, and is 

 generally found attached to the stems and under 

 surface of the leaves of the Common Lemna minor 

 or Duckweed. 



But a still more elegant species is the Vorti- 

 celia racemosa. It is found during the summer 

 months in clear stagnant waters, attached to the 

 stalks of the smaller water plants and other objects; 

 to the naked eye the whole groupe, on account of 

 the great number of individuals composing it, is 

 distinctly visible, in the form of a small whitish 

 spot, resembling a kind of slime or mouldiness, 

 but when placed under the microscope in a drop 

 of water on a glass, its extraordinary structure is 



