Marvels of Pond-Life. 61 



venience. The pieces of glass are stuck together with 

 marine glue, and a very simple contrivance enables the 

 plants or other objects to be pressed near the front, and 

 thus brought into better view. A strip of glass, rather 

 narrower than the width of the trough, is dropped into 

 it, and allowed to fall to the bottom. Then a piece of 

 glass rather shorter than the trough, and rather higher 

 than its front side, is placed so as to slope from the 

 front of the bottom towards the back at the top. The 

 piece of glass first dropped in keeps it in the right 

 position, and the trough is thus made into a V-shaped 

 vessel, wide at the top and gradually narrowing. Any 

 object then placed in it will fall till it fits some part of 

 the V, where it will remain for observation. A small 

 wedge of cork enables the moveable piece of glass to 

 be thrown forwards, until it assumes any angle, or is 

 brought parallel to the front of the trough. 



A power of five or six hundred diameters generally 

 enables a movement of small globules to be seen at the 

 extremity of the lobes of the Floscule, and the gizzard 

 may be made plain by dissolving the rest of the creature 

 in a drop of solution of caustic potash. It also becomes 

 more visible as the supply of food falls short. Mr. 

 (jrosse describes the body as " lined with a yellowish 

 vascular membrane," and young specimens exhibit two 

 red eyes, which may or may not be found in adults. 

 When these eyes of Rotifers are not readily conspicuous, 

 they must be sought for by opaque illumination, or by 

 the dark-ground method which, especially with the 

 parabola, is successful in bringing them out. 



Naturalists, and possibly the specimens also, do not 



