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gone unreported in the literature. Minckley (1983) reported that razorbacks reared at Willow Beach NFH attained sexual maturity at six years when the fish were 14 to 16 inches in length. Fish less than 14 inches total length were not mature. Two-year-old male razorbacks reared at Dexter NFH were sexually mature and running milt in 1983. Microscopic examination of the milt showed it to contain viable spermatozoa. These fish averaged 15.6 inches and 1.6 pounds. Examination of female razorbacks (16.2 inches, 1.9 pounds) showed the ovaries to contain developing eggs; later in the summer a few of the females were releasing a few eggs. It appears that sexual maturation of razorback sucker is most closely related to size but males will mature in two years and females possibly in two years but at least in three years when the fish are well fed and grow rapidly. Development of secondary sexual characteristics in female razorbacks is monitored periodically through January and frequently as spawning approaches in February. At Dexter females become gravid as the water temperature approaches 500F and are usually ready to spawn when the temperature reaches 550F. As they ripen their abdomen and pregenital area softens and the genital papillae enlarges considerably. Ripe male razorbacks develop large tubercles on their anal and caudal fins while females occasional develop a few tubercles on the same fins. Females ripen at different times and the "best looking" fish are selected for each spawning period. It takes five or six weeks to complete spawning of all females. Female razorbacks are injected with human chorionic gonado- tropin (HCG) to finalize maturation and to stimulate ovulation of maturated eggs. Inslee (in press) determined that 100 International Units (IU) of HCG per pound of body weight injected intramuscularly to be the preferred hormone, dosage and site of