RIVER GARDENS; 



which they are placed, and that their natural colours 

 are frequently the result of the colour of the soil 

 forming the beds of their native streams. A simi- 

 lar kind of susceptibility is also found in other 

 fishes a circumstance which is, in fact, a means of 

 defence, as rendering them less conspicuous in the 

 water. Dr. Stark tells us that he once observed a 

 shoal of Flounders, on the flat sandy part of the 

 coast of Holland, so exactly the colour of the sand 

 over which they were swimming, as to be hardly 

 distinguishable from it. 



But I must hasten to describe the most interest- 

 ing instincts that honourably distinguish the little 

 Stickleback. I of course allude to those connected 

 with his habits of nidification. 



Nest-architecture is generally thought to be 

 almost entirely confined to birds; the number of 

 quadrupeds which attempt nest-building being very 

 few, and those few not remarkable for any special 

 skill. Indeed, even in these cases, such as the "nest " 

 of the Squirrel, the Eield-mouse, the Habbit, and a 

 few others, it is rather a "bed" for the young, than a 

 receptacle for the deposition and production of eggs, 

 which is alone the character of a true nest. 



The only true nests, therefore, except those of 

 birds, are constructed by fish. This, consider- 



