Changes in proteolytic enzyme concentration were measured between the 2nd-3rd and 3rd-4th, larval ecdyses (I.e. during one complete molt) in fed and starved mosquitoes. Weight changes were determined during the same period. Growth in enzyme-secreting tissue appears to be isogonic with total growth. Enzyme secretion is not interrupted by molting and ecdysis. Since enzyme secretion is apparently continuous with feeding and terminates abruptly in the absence of food, it is regulated in close conjunction with feeding.