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characteristic of males was a greater protrusion of the genital papilla. We again checked the fish on June 10th and obtained seven eggs from fish tagged number 987. Tubercles had spread over the entire body of the males, with the exception of the abdominal area. Tubercles were particularly heavy on the head and the dorsal surface of the pectoral fins. We continued to check the fish every few days until Monday, the 24th of June. At this time, we took seventy very small eggs from female number 987. The females were injected with chorionic gonadotophin, 900 units per pound. The males were very ripe. Milt was the consistency of very thick cream. There were no positive results for the remainder of the week. Eggs were observed in the genital papilla of number 982, but could not be expelled. The fi sh \'Iere not checked over the weekend. On Monday morning, one week after hormone injection, eggs were discovered in the gravel. Egg development indicated spawning had probably occurred some time during the previous night. The eggs were scattered over an area approximately four feet by eight feet, in water five-to twelve inches deep. Water temperature was 72oF. Eggs appeared to be adhesive. Some were in clumps, and others adhered.to gravel. Stirring the gravel by hand over a square foot area would dislodge several hundred eggs. These could easily be collected in a fine mesh hand net. Severa 1 thousand were co 11 ected in thi s manner. Some of these \-,ere placed in a fine mesh net with gravel and left in the raceway. Others were moved to a hatchery tanl< and placed on a screened tray with water tempera- tures of 680F. Still others were placed in a floating net in raceway Bl, water temperature 660F. This raceway was set up for rearing the fry several weeks in advance, and contained good plankton bloom. Samples were removed from the net in the original spawning area tYlice daily. Mortality of eggs in the floating net was high, probably due to suffocation. Eggs on the screened tray in the hatchery continue to develop. Samples collected from the original spawning area had well pigmented eyes at 9:30 A.M. on the 4th of July. Samples collected that evening, at 8:00 P.M., were hatching. Eggs on the tray in the hatchery were hatching at 7:00 A.M. the next day. Eggs were 2.0 millimeters in diameter. Newly hatched fry, 6.5 millimeters in length. Our facility in the hatchery building for the eggs and first few weeks of fry development is identical to that used for the razorback suckers. This consists of a standard hatchery concrete tank three feet wide by fifteen feet long. The tank was filled with fresh 550F. river water to a depth of two feet. Flow to the tank was then turned off to allow the water temperature to ~Ise. A fine screened tray, three feet square, was placed a few inches under the surface. One twenty-four inch carbon stone was placed on the bottom of the tank at each end af the tray. This provides aeration and a current of water throug~ the tray. Since I.just discu3sed the hatching and early frl facilities for our ~~7n~h~~ks. Iwill oroceed to thi~ species.