JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.

Cysticercoids of Hymenolepis microstoma, Hymenolepis nana, and Hymenolepis diminuta were examined for their ability to excyst in vitro after being stored in balanced salt solution, distilled water, or the bodies of dead hosts (Tribolium confusum). The number capable of excysting decreased as the duration of the storage period was increased but the rate of decrease varied with the storage medium and was invariably slower when the parasites were stored at 4 °C than when they were kept at 22 °C. The combination of storage medium and temperature that produced the slowest rate of decrease in the ability of the parasites to excyst varied according to species.