The Animalcules, continued. 127 



elements that surround them, the latter from sub- 

 stances already organized which afford a method of 

 drawing a distinction; but, as Mr. Slack tells us, 

 " the learned do by no means agree " on the question 

 " What is an animal ? and how does it differ from a 

 vegetable ? " and he amusingly characterises the dif- 

 ference as being " observable enough if we compare a 

 hippopotamus with a cabbage, but which grows 

 ' small by degrees and beautifully less/ as we con- 

 template lower forms." 



Something of the interest of a riddle, then, 

 attaches to these researches; but, more than this, 

 there is an especial charm in the contemplation of 

 these simply-framed plants and animals, which seems 

 to conduct us near to the elementary law or principle 

 on which all organized beings are formed.* 



Passing over numbers 6, 7, and 8 of my list, 

 which I did not re-examine, but 

 which I believe to have been, the 

 first a Paramecium, characteris- 

 tically covered with long rows of 

 cilia, which I described as "hairs," 

 and the last two members of the 

 Kolpod family, there remain the 

 rotifer, the swan-like animalcules, 

 and "animated straw-mat." This 

 last was Stylonichia, and I find NO. 17. Stylonicliia. 

 that Mr. Slack makes mention 

 of its bristles and its comma-like appendages, both 

 of which are developments of cilia, and known as 



* See " Marvels of Pond-Life,'* Introduction, and chap. xiii. 



