On Stocking. 59 



into account and an ample bye-wash provided. 

 The inlet of a pond is easily screened against trout 

 ascending a very slight fall over a ledge into 

 shallow water is sufficient ; trout cannot jump out 

 of shallow water as they can out of deep ; but 

 the outlet screen presents more difficulty arid 

 should be large enough to pass all the water in 

 time of flood, and deep enough below the outlet 

 to pass all the water in time of frost. 



The best water-plants for ponds must vary in 

 every locality, generally speaking, watercress-beds 

 in connection with the inlet give excellent results. 



The depth of the pond effects the gross weight of 

 trout the pond can rear more than anything else: 

 with shade, a pond only one foot deep will hold a 

 few small trout, but the largest trout require even 

 with shade, at least six feet of depth of water. 



Ponds sometimes get very milky in the early 

 winter, and as all conditions of water have impor- 

 tant bearings on trout life, I note -the observations 

 here, so that others may consider the question. 

 I suggest as an explanation the probability that 

 the sudden chilling of a thick layer of water at the 

 surface, and its consequent descent to the bottom 

 at a time when the bottom layer of water and in- 

 fraposed mud are at a temperature of at least 

 40 Fahr., may cause the finer particles of sediment 

 to rise throughout the pond and produce the ap- 

 pearance of milkiness. 



