A dependable source of quality fish spawn is a fundamental prerequisite for fish culture development. This is especially important inasmuch as most of the cultivable species do not breed in confined waters. Also, sport fisheries are gaining greater popularity, and subsequently the fish supply is being taxed. Still another need for fish spawn is in the ever increasing demand for bait minnows. Also, the construction of more and more dams has resulted in insurmountable obstacles for ascending and descending fish, which may ultimately result in complete destruction of some fisheries. Thus some measure of artificial propagation will have to be taken to safegaurd our valuable fishery resources. A partial solution to this problem of supplementing natural propagation is that of inducing the fish to spawn artificially in the hatchery. A method of doing this is by stimulating fish to breed by the use of pituitary hormones. Those pituitary hormone-containing glands are often collected under a variety of field conditions which may involve considerable effort, time, and money. Therefore,, it was my objective in this study to develop a practical refined assay on hormones using as small an amount as possible of the crude extract of pituitary suspension, and to make it simple enough that every lay fisheries man ,dll be able to apply it, thus meeting his demand for quality fish eggs in his own hatchery when he needs it most.