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pensive apparatus is necessary to aerate the water in which, in a 

 small space, numerous animals are confined, amountinfi,- often, in 

 the case of the tanks in this building, to many hundreds in a 

 single compartment. 



The aeration of the water in the ocean is effected by the 

 constant lashing of the waves into foam, and it is well known 

 that during periods of long continued calm, especially in the 

 tropics, multitudes of creatures perish, and the surface of the water 

 is covered with their dead bodies, and the air above is tainted by 

 the products of decomposition. 



An aquarium, therefore, should be so constructed that by 

 artificial means the same aeration takes place as is produced in 

 the sea by natural means. 



All this has been, in the Crystal Palace aquarium, carefully 

 thought out and thoroughly provided for ; and I cannot but 

 consider that the result is a triumph of intellect which reflects 

 the highest credit on the designer and constructor. 



Nature has been followed, and her suggestions have been 

 adopted. 



For all the details of the construction of this aquarium, and for 

 a complete description of the creatures in the several tanks, I 

 must refer you to Mr. Lloyd's Official Handbook, in which the 

 subject is admirably treated. 



I shall confine my observations to some of the ideas which 

 have arisen in my own mind when examining the creatures in 

 this aquarium. 



I now propose to run rapidly through the different classes of 

 animals in the aquarium, and to draw your attention to some of 

 the most remarkable facts connected with their organization and 

 habits. 



Beginning with the highest forms, the first creature I have to 

 notice is well worthy of attention. 



The Axolotl {Siredon pisciformis) belongs to that class of animals 

 which in some respects are intermediate between Reptiles and 

 Fishes. They commence life by breathing water through gills, 

 and are Fishes ; they then undergo a metamorphosis, lose these 

 gills, acquire lungs, and may be said to be Reptiles. The Frog, 

 Toad, and Newt are representatives of the class. 



There are, however, in the class some which do not lose their 

 gills, but which breathe water during the whole of their existence, 

 and, until quite recently, the Axolotl was thought to be a peren- 



