PREFACE. 



, WAS always fond of Natural History, and wHle 

 I was a boy I frequently looked forward to one day 

 possessing an aquarium so large tliat I.jniglit collect 

 as many aquatic creatures as I liked from the neigtbouring 

 ponds and streams, place them all togetber in my tank, and 

 then make myself q.uite happy by watching the habits and 

 the changes of my captives. But, aias ! in course of time. 

 I foun<i, as so many find, that the realisation of one's hopes 

 does not always bring with it the anticipated pleasure. Tor 

 when I did eventually own as big and — as appeared to me at 

 that time— as suitable an aquarium as I could wish for, and 

 when I did stock it with many curious and (to my mind) 

 interesting animals, I was, after all, not very happy, nor even 

 content ; far from it. Th* Sticklebacks and the aquatic Spiders 

 would not build their nests side by side ;. the Bytiscus marginalis 

 absolutely refused to live On anything like friendly terms with 

 the Minnows; the Snajls while crawling over my most valued 

 plants were not able to refrain from devouring them and 

 ruining them ; the water would not keep' bright, nor the glass 

 of the tank clear, and my patience was soi-ely tried. I bought 

 or borrowed whatever books I could upon aquarium a-nd kin- 

 dred matters, but I was aot able to obtain a.11 the information 

 I required. Then I . attempted to find out by experiment 



