While rearing Galleria mellonella L. to further studies by Mankiewicz (1952) on the wax splitting enzymes which they produce and the action of these enzymes on Myctobacterium tuberculosis, it proved difficult to secure a constant supply of honey and comb, the natural food and habitat of this species. Haydak's (1936) summary of earlier work on rearing this wax moth indicated that success had been attained with several artificial media. The writers, therefore, tried an artificial medium and attempted to assess its effect on the nature of the enzymes later extracted from the larvae.