MILNER FISHERIES OF THE GREAT LAKES. 27 



fastened to the box, for convenience in handling, and to prevent any 

 necessity for throwing it out of level while carrying it. The zinc can 

 contains ten trays, each of which carries fifty-four small boxes, two 

 inches square and two inches deep, set in compartments, each compart- 

 ment having an inch hole cut in the center. The partitions between the 

 compartments are just high enough (about five-eighths of an inch) to 

 inclose the bottom of a box, and hold it firmly in its place. Ko covers 

 are provided for the boxes, but a large cover can be fitted to the zinc 

 can, and a lid, with a good lock, is fitted to the outside box. The bot- 

 toms of all the little boxes are perforated, the position of the holes 

 being directly over the circular hole in the compartment of the tray. 

 The zinc can has also holes in the bottom, and the wooden box has 

 three-quarter inch holes bored on each side, near the bottom, so that 

 there is drainage for the surplus water of all the boxes, and a free cir- 

 culation of air throughout, which is deemed important by some of the 

 fish-culturists. 



At the island the most perfect arrangements were provided by Mr, 

 George Clark for obtaining the spawn. Two tanks of about five feet 

 diameter were placed at the edge of the shore and partly filled with 

 water. As soon as the bag of the seine was on the beach the men 

 picked up the white-fish and put them immediately into the tanks. The 

 pans for impregnation were close at hand, and as one man lifted the 

 fish above the water in a dip-net, another took it from the net, and with 

 his right hand over the head of the fish and his left around the tail he 

 held it over the pan, standing at the left of the operator. The left 

 hand of the operator was put against the back of the fish and the right 

 hand used in manipulating the abdomen. It was found that to induce 

 the eggs to fiow freely from a fully ripe female, all that was necessary 

 was to apply a gentle pressure Just behind the pectoral fins, just where 

 the nudging and bunting of the head of the male fish is applied while 

 racing her through the water. Not until the greater part of the free 

 eggs had fallen into the pan was it necessary to slide the hand along 

 the abdomen. The free eggs came away in a steady, li(iuid stream, but 

 from a fish partially ripe their extrusion was slow, and in masses com- 

 paratively dry, that did not freely disengage themselves from the fish 

 and fall into the i)an. 



The female exhibited the most indications of pain when the pressure 

 was applied in the vicinity of the ovipore. The milt from the male will 

 flow in from one to three jets by pressure in the vicinity of the anus. 



The method employed by Mr. X. ^Y. Clark was that which was origi- 

 nal with Mr. Seth Green, using the smallest quantity of water possible. 

 The eggs, after falling into the pan, and the milt having been stirred up 

 with the water, were allowed to stand about half an hour, when the 

 milt and water were poured off and the eggs carefully rinsed through 

 several changes of water. A small (luantity of water was left with the 

 eggs when they were i^erfectly clean. 



