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•';~ <w at about the fourth day or just prior to the start of eggs hatching. Water quality from the decaying eggs may pose a problem to hatching Larvae. A great advantage to the Beath incubator will be the ease in treating eggs for fungus, and the availability of the incubating eggs for observations. Although the number of eggs that can be hatched per try has not been deter- mined the suggested starting point is 10,000 to 20,000 per tray. The heavy fungal growth that developed in the incubator just prior to hatching prompted an attempt to seperate good eggs from bad eggs that were fungused. After the eggs had started hatching, the eggs on the trays were placed in a McDonald hatching jar. The bad eggs and fungused eggs were lighter than viable eggs or hatched fry, tYius the fungused and bad eggs were carried out of the jar with the water flow and the viable products were retained. During the seperation process of four hours, more than 90% of the eggs hatched. After the seperation process, the eggs and larvae were placed in a six foot circular tank, as previously described, to allow the fry to develop to the swim-up stage. The fry started swimming out of the circular tank drain on the 14th day. They were caught in a IZ" x 16" x 15' tank with a fine screen of saran cloth to retain the fry. Fry were removed daily from this tank and trans- ferred to a holding house tank to be offered a prepared ration. Fry swam out of the circular tank for four days. A total of 28,500 swim-up fry were obtained from the eggs that incubated in the Heath incubator. Or an average of 14,250 per, female. Fungus Studies The viable three and four day old eggs that were treated with formalin at 1:75, to 1:600 for 5,'10 and 15 minutes showed no mortalities from the ,. treatment: Eggs treated with 1:50 formalin for 10 minutes had a 54% mor- tality rate for three day old eggs and a 33% loss of the four day eggs. 14