78 DROPS OF WATER. 



bodies, found principally in the sea, and too com- 

 plicated to admit of description here ; but I 

 must mention the genus Acineta, which has been 

 added to the Bacillarice. It may be frequently 

 noticed on the stalks of Lemna, and, being 

 extremely pretty, shall be described. The body 

 is affixed by a short stalk, is small, and round 

 or bell-shaped, with numerous rays project- 

 ing from it in various directions, each appear- 

 ing to have a slight knob at the end ; these 

 rays do not vibrate, but are said to be retractile. 

 This I have not observed, for I never could trace 

 movement in any part of this singular little 

 being. It is nearly transparent, very small, and 

 may be almost compared to a pin-cushion with 

 pins in it ready for use, as the knobbed rays 



