496 INFUSORIA. 



elongated into threads, HIMANTOPES. The second tribe consists of those 

 which exhibit no external organ whatever, if we except a tail. In CERCARIA, 

 Muller., the oval body is, in fact, terminated by a thread. To this genus 

 belong (among others) those animalcules which are observed in the semen of 

 various animals, and on which so many fansta&tic theories have been founded. 



When this thread is forked, as is sometimes the case, we have the 

 FURCOCERCA of Lamarck. 



VJBUIO, Midler, 



Where the body is round and slender like a bit of thread. 



It is to this genus that belong the 



V. glutinis et aceti, or the pretended eels that are seen in vinegar and paste. 

 Those that inhabit the former are frequently perceptible to the naked eye. It 

 is asserted that they change their skin, consist of two sexes, produce living 

 young ones in summer, and eggs in autumn. Freezing will not kill them. 

 The others make their appearance in diluted paste. 



The most singular genus of the whole is the PROTEUS, Lin. No determinate 

 form can be assigned to them ; their figure changes every instant, and is some- 

 times rounded, sometimes divided and subdivided into thongs, in the most odd 

 and singular manner. MONAS, Mull. The Monades, viewed under the 

 microscope, resemble points moving with great rapidity, although destitute of 

 any apparent organ of motion. VOLVOX. A globular body, revolving on its 

 axis, and frequently containing smaller globules, which are doubtless the 

 continuation of the race. 



