Tissue cultures were secured of the following species: 2 Coprinus atramentarius Fries, C. comatus Fries, C. fimetarius macrorhizus Fries, C. micaceus Fries, C. plicatilis Fries, C. quadrifidus Peck, C. radians Fries, C. radiatus Fries, C. semilantanus Peck, Galera crispa Longyear, G. tenera (Fries) Quel., Panaeolus campanulatus (Fries) Quel., P. retirugis (Fries) Quel., P. solidipes (Fries) Quel., Psilocybe subviscida Peck, Stropharia semiglobata (Fries) Quel. The stock cultures of these fungi were grown on potato maltextract agar, and transfers were made from this to the eightyseven media that were tested either in test-tubes or Erlenmeyer flasks for their value for the growth of the fungi and the production of fruiting-bodies. There were five general types of media: those consisting of more or less unchanged, natural substances; those containing some known carbohydrate for the food supply; those consistipg of potato malt-extract agar to which were added poisons or weak antiseptics; those consisting of potato malt-extract agar to which