CLASSIFICATION. 71 



nating in a ciliated cup, thus forming an elegant little 

 branched Vorticella. It differed from the one I first men- 

 tioned, not only by being much more minute and more fas- 

 tigiate, the first being rather dichotomous and the terminat- 

 ing cells placed at different heights, but also as being less 

 lively, not having the habit of suddenly collapsing, but con- 

 tinuing in an unfolded state. " Vorticella, in general, can 

 bend and turn and twist in all directions ; they can almost 

 cast a knot on their tender and delicate stems. Microscopic 

 shrubs composed of similar animals, hundreds of campanu- 

 late Hy&ra terminating their extremities, while at their 

 highest enjoyment of full expansion in some favourable posi- 

 tion, will suddenly collapse on a momentary alarm, crouching 

 close down to its root in absolute quiescence. Then, as if 

 relieved from the apprehension of danger, they rise again to 

 display their beautiful proportions." 



What struck me as remarkable in this " minim," was, 

 that it seemed indifferent as to its element, whether fresh or 

 salt water; for having kept fresh-water in a tumbler for 

 some weeks, I was surprised to find the Vorticella as nume- 

 rous in it as in the sea-water. To all appearance they were 

 the same species, and yet had they been examined with a 

 microscope of higher power, a difference might have been 



4 



