254 APPENDIX. 



The hands of the operator can be seen (No. 1) 

 placing in the framework of glass rods (which rests 

 upon projections in the inside of the troughs, made 

 to receive it when in its place). The eggs should be 

 placed upon these rods, and left to hatch out. 



The lower tank (No. 2) represents the fish eggs 

 resting upon gravel — as good, but not as pretty, 

 a manner of treating them. The water from the 

 tap above must be flowing incessantly with a gentle, 

 but not rapid, stream. You should have boards 

 made to fit over the tops of the troughs while the 

 eggs are being developed into fish. 



I am in communication with a London manu- 

 facturer as regards making these troughs, and hope 

 that they will be obtainable at a small price by the 

 next fish- egg season. 



The tanks can be made of zinc (as mine are in 

 "The Field" window), viz., two feet long, five inches 

 wide, four inches deep, with one side of glass. These 

 can be fixed by means of blocks of wood, one above 

 the other, end over end — the same idea, on a 

 small scale, as is given for the outdoor apparatus. 

 If the water does not run freely from the tubes, 

 they should be lengthened by an inch or two of 

 india-rubber pipe fastened over them. 



Fig. 3 represents what I call the " catcher,^' a 

 most useful instrument for moving the eggs mthout 

 touching them. Place the finger on the end of the 

 straight part of the tube, immerse it in the water, 

 and bring the lower end opposite the egg or im- 

 purity you wish to remove. When the finger is 

 withdrawn the water rushes instantly into the 

 tube, and with it the object, fish, egg, or weed you 

 wish to withdraw. These catchers were designed 



