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The cyclopamine used in this experiment was pre-dissolved in ethanol at a concentration of 1 mg per ml. With a molecular weight of 409.61 grams per mole, this is a 0.00244 molar solution. The calculations for determining the amount needed to reach a certain molarity of the Ringer's solution were fairly simple, though the ethanol had the potential to complicate the experiment. To account for the toxicity of ethanol, this expermiment was conducted in two phases. In both phases the embryos (10 per sample for part 1, 15 per sample for part 2) were exposed to their designated concentrations of cyclopamine for 24 hours, at which time their Ringer's solution was replaced with fresh solution without the cyclopamine/ethanol mixture. The embryos were photographed every day as they developed. In the first phase, the cyclopamine solution was used at varying concentrations (listed below in micromoles). This table showed that at any concentration greater than 100 micromoles, the embryos would not survive, so the second part of the experiment was changed to meet our new data.