36 THE AQUAVIVAKIUM. 



ALG.E. The Algce are called Seaweeds, because the 

 great mass of them are found in the sea, but 

 there is a little group of them sometimes called 

 Crow-silks (Confervacece) which are found in 

 fresh water. Some of these are not very orna- 

 mental in the Aquavivarium, in fact they are 

 its weeds, its pests, and will sorely trouble the 

 amateur. He will not be able to pull them up 

 a plant at a time, as he does the chickweed and 

 groundsel in his garden, and they will frequently 

 tax his ingenuity to get rid of them. They are 

 most of them cellular plants without branches, 

 consisting of minute cells which have been laid 

 end to end for several inches in length. Their 

 beauties do not come fully out as they float 

 through the water, but under the microscope 

 many of them are charming. The Yoke threads 

 (Zygncemata) present the most elegant markings 

 in their cells, whilst the Quiverworts (Oscilla- 

 toriece) attract attention by their never-ceasing 

 movements. Those who have a microscope will 

 do well to keep a vessel especially for these 

 beautiful Algse, and I promise them a rich 

 harvest of delight in examining their beautiful 

 forms and investigating their functions. 



Here, then, we must terminate our account of 

 Plants for the Aquavivarium, not for the want of 

 matter but the want of space. I only hope that 

 what I have said above may tempt the reader to 

 study the Vegetable Kingdom more in detail than 

 can be done by observing the pets of the Aqua- 

 vivarium. 



