302 THE MICROSCOPE. 



VIBRIO Vibriones. In this family Ehrenberg includes 

 the well-known eels in paste and vinegar, both of which 

 are now placed in a different class. 



Vibrio spirilla, Trembling animalcules, when motionless, 

 are seen as very minute hairs ; but when they exert the 

 powers of locomotion, they take a spiral form, like the 

 threads of a fine screw, and by undulations wind them- 

 selves through the water with rapidity. Each apparent 

 hair is a collection of animals bound together by a pliant 

 band; thus, as they are individually so small, little is 

 known of their structure. Still they form very interesting 

 objects to view ; their very minuteness claiming attention, 

 while their activity and motions excite surprise. The 

 species are numerous, as represented at No. 1, fig. 175. One 

 in particular has been the especial subject of investigation 

 by the medical microscopist, is somewhat of an oval 

 shape, and is quickly developed in diseased structure ; 

 doubtless it precedes, or leads to, the entire destruction of 

 the tissue it is found in. This shape of the curious little 

 animalcule, it should be observed, is confined to animal 

 substances ; whereas the long, or hair-shaped, is generally 

 to be met with in all disorganised vegetable substances. 



These hair-like animalcules were very accurately de- 

 scribed by Baker, who ascribes the discovery of them to 

 Mr. Anderson. He says : " They were discovered in a 

 large ditch running into a river near Norwich, the bottom 

 of which was covered with them to some thickness; when 

 first examined, being motionless, they were taken for 

 vegetable fibres ; but on keeping them under the micro- 

 scope, and occasionally viewing them, they were seen to 

 move in various forms." Some Confervce present a re- 

 markable motion, like moving spiral threads, but are 

 much larger than the preceding. 



ASTASI^EA. Astasia, signifying without a station, in 

 contradistinction to those living in groups, is the term 

 given to a kind of crimson- coloured animalcule, the 350th 

 of an inch in length, that exist in enormous numbers, and 

 give the waters in which they live the appearance of their 

 bodies. Ehrenberg describes several varieties of this family. 

 , Astasia Viridis. On the surface of ponds and stagnant 

 waters is sometimes seen a crimson covering, which, when 



