i8o HIDDEN BEAUTIES OF NATURE 



the general opinion that rotifer was endowed with 

 sight only in the days of its youth, that when it 

 settled down finally and began to construct its house 

 its eyes disappeared. A careful examination does 

 not bear out this erroneous supposition. The position 

 of the eyes is changed ; but occasionally, with favour- 

 able conditions of illumination and position, the tiny 

 brilliant specks can be seen in the adult forms. 

 Besides its behaviour in selecting materials for brick- 

 making, its quickness in rejecting substances unfit for 

 food or for manufacture, its knowledge as to where 

 the succeeding bricks in each row are to be laid, all 

 point to the fact that the creature has eyes, and good 

 ones into the bargain. Ever so many duties are 

 carried on at the same time by friend rotifer. It 

 collects clay held in suspense in the surrounding pond 

 water, it collects food, it separates building material 

 from food, and rejects worthless substances, it grinds 

 its food, moulds the brick, and places it in position. 

 To make the brick impervious to the dissolving 

 powers of the water, it must be coated or mixed with 

 some mysterious substance provided by the creature 

 itself. And so durable does the cement make the 

 fragment, that it lasts long after its intelligent tenant 

 has passed away. The word 'intelligent' may be 

 objected to, but I cannot look at this creature with- 

 out feeling that it is endowed with intelligence of a 

 high order, notwithstanding its extreme minuteness. 



The movements of the cilia bordering the disc are 

 quite under the control of the creature, for they show 



