Abstract
Trials of cultivating Citrullus colocynthis (L.) Schrad. were carried out in the Medicinal Plant Garden of the Medical Academy to Wrocław. The seeds were obtained from Bucarest and stored for one year. The plants obtained from those seeds developed well, produced flowers and fruited. The seeds germinated in darknees in about 90%. Light distinctly inhibited germination. Urease activity was determinated initially in the seeds by the method of Sumner. One kilogram of whole seeds has an activity of about 12000 Summer units.