The enzyme, hyaluronidase, detected in crude venom was active over a pH range of 4-9 and was stable to at least a 72 hr storage at 4 degrees C. Preparative electrofocusing indicated a pI value for this enzyme between 9.5 and 10.2. Hyaluronidase partially purified by gel-filtration chromatography was evaluated as a spreading factor for dermonecrosis provoked by the nematocyst venom on depilated rats. The spread of dermonecrosis increased regardless of the presence or absence of hyaluronidase. Hemolytic activity of crude venom was assayed on erythrocyte suspensions from various sources. Pig and rat erythrocytes were the most sensitive to the hemolysin of the erythrocytes tested. The pH optima for the hemolysin was 8.3. Trypsinized rat erythrocytes were more susceptible to hemolysis induced by venom than non-trypsinized cells. The monovalent and divalent cations KCl, BaCl2, CaCl2, and MgCl2 were inhibitory to hemolytic activity induced by crude venom. The hemolysin partially purified by gel-filtration chromatography tested for stability after overnight storage at 4 degrees C and -70 degrees C indicated a 50% and 75% loss of activity, respectively, in comparison to the hemolytic activity recovered directly after gel-filtration chromatography.