37 



CHAPTER Y. 



OF THE ANIMALS TO BE KEPT IN THE 

 FRESH AQUA VIVARIUM. 



THE water having become clear, and the plants 

 beginning to grow, we must now consider what 

 animals we ought to put into our Aquavivariuin. 

 I would not recommend persons to be very particu- 

 lar on this point. Some animals are undoubtedly 

 prettier and more curious in their habits than others, 

 but those which can be most easily procured will 

 always be found interesting. I shall therefore 

 refer to the more common forms of British 

 animals, which can be secured for display in the 

 Water- vi vary. With the same object in view as 

 when treating of plants, I shall speak of animals 

 according to their natural-history classification. 

 All animals are divided into those with back- 

 bones (Vertebrata) and those without these organs 

 (Invertebrates). 



The animals with backbones contain five classes : 

 Mammals, Birds, Reptiles, Batrachians, and 

 Fishes. With the first three we shall have nothing 

 to do ; for although it is possible to keep seals, 

 porpoises, and even whales in our menageries, few 

 of my readers will attempt experiments on so grand 

 a scale ; nor will they probably try to domesticate 

 young crocodiles or alligators ; so that we have only 

 Batrachians and Fishes among the Vertebrate ani- 

 mals to speak of. The backbone-less animals are 

 very numerous, and are divided into three great 

 groups, all of which we shall find represented in 

 our A quavivarium. 



