Marvels of Pond-Life. 23 



Another piece of apparatus in tliis family, but not 

 confined to it, is the so-called nucleus, uhich in this 

 case is of a horseshoe shape and granular texture, 

 and greater solidity than the surrounding parts. The 

 functions of this organ formed the subject of various 

 conjectures, but it is now generally held to be an 

 ovary. 



In common with many of the lower animals, the 

 Vorticellids have three ways of multiplying their race. 

 One by fission, or division of their bodies : another by 



• Vorticella microstoma, in process of encystment, 300 linear ; in the 

 last the inclosing tunic is plainly developed. — Stein. 



^?<c?5, somewhat analogous to those of plants; and another 

 by reproductive germs. These processes will come 

 again under our notice, and we shall leave the Vorti- 

 cellids for the present by observing that if they are 

 fed with a very small quantity of indigo or carmine, 

 the vacuoles or spaces, into which their nutriment 

 passes, will be clearly observed. Ehrenberg thought 

 in these and similar creatures that every vacuole 

 was a distinct stomach, and that all the stomachs 

 were connected by an intestinal canal ; hence his name 



