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decaying vegetation, retains the rain water and prevents it 

 from rushing to the rivers and the sea, while it gives it off 

 to these slowly and steadily. It acts like a great sieve and 

 retains the fine particles of the soil, which the influence of 

 the air and sun, the frost and rain, and the action of the 

 numberless roots have decomposed, thereby fertilising the 

 land and forming a layer of mould or humus, in which insects, 

 worms, larvae, and other animalcules live and breed. 



In his most interesting paper on fish diseases, Prof. 

 Huxley said that drought or flood did not seem to affect 

 the Saprolegnia, but that a steady flow was beneficial to 

 the fish. 



Mr. Wilmot, in the following discussion, pointed out that 

 the disease nearly always appeared where the regularity of 

 the supply of water had been disturbed by the destruction 

 of the forests. 



I presume, therefore, that both these learned and prac- 

 tical gentlemen will agree with me in the importance of 

 the forest protection as a means of preserving the health of 

 the fishes. 



The branchlets, leaves, decaying and decayed vegetation, 

 produce a vast amount of nourishment for the fish, and one 

 most agreeable to them. Each breeze drops into the 

 water numberless grubs, caterpillars, beetles, flies, and 

 other insects, the food most relished by the fishes, while from 

 the banks and roots worms and grubs are constantly sup- 

 plying them with delicacies. 



The shade of the overhanging trees is also agreeable to 

 the fish, and one needs only place a board in a stream and 

 see the fish gather underneath it to be convinced of this. 

 We all know that a shady deep pool is a good place in 

 which to seek for fish, and have often observed the predilec- 

 tion fish have for the shady side of a stream. But not 



