Various properties of coriamyrtin were found to be similar to those of picrotoxinin and, therefore, their comparative examination was carried out. A structural formula of coriamyrtin was assumed on the basis of the formula given for picrotoxinine by Conroy by which the carbon skeleton formed a part of steroidal skeleton as in picrotoxinin and the reductive action of coriamyrtin was assumed to be due to its acetal group. Comparison of the infrared absorption spectra of coriamyrtin and its derivatives with those of picrotoxinin and its derivatives endorsed the assumed structure for coriamyrtin.