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GLASS JARS. A pretty and ornamental modification 

 of the Holton box, not essentially differing from it on 

 principle, can be made by the use of glass, and will 

 answer on a moderate scale. It consists of round glass 

 jars filled with trays with the water entering at the 

 bottom, which should be cast in the shape of a funnel to 

 which is attached an India rubber pipe. The water 

 passes out above through another pipe to the bottom of 

 the next, and so on. The advantages claimed for this 

 arrangement are the neatness, beauty and cleanliness, 

 and the ease with which the eggs can be watched and 

 studied at all times. It is well to have the supply pipe 

 smaller than the connecting pipes between the jars, for 

 fear of overflow in case of accidental obstruction, and 

 from the first there should be a gradual descent, each jar 

 standing a little lower than the one preceding it. When 

 it is desirable to empty any jar it can be done with a 

 tube of rubber used as a syphon, the supply of water 

 being shut off. By drawing off the water into a basin, 

 any young fish carried with it may be saved. 



SELF-PICKER. Another modification of the Holton 

 box was made at the state establishment. It has been 

 called a " self picker." It consists simply in removing 

 all the trays and placing the piece of tin over the hole 

 through which the water enters, which should be in the 

 center of the bottom in such a way 'as to force the water 

 to rise gently on all sides close to the edges. The box is 

 shaped so that the sides converge towards this center 

 and the water makes a moderate current along them up- 

 wards. The eggs which are placed loosely in the box 

 are kept in a gentle bubbling or boiling motion by this 

 arrangement. They are caught by the current, carried 

 upward, and then dropping into an eddy, descend to be 

 again whirled upward. Wlien the fish hatch the gener- 



