The importance of ticks as transmitting agents of various diseases of man and animals continues to become more manifest as our knowledge of them increases. Although these annoying and dangerous parasites occur in practically all climatic zones they are much more numerous in the subtropical and tropical regions. In Panama the ticks are extremely abundant as regard numbers and species, being found on nearly all varieties of domestic and wild animals, birds, snakes, lizards, toads, tortoises, etc., and also attacking man. The several tick-transmitted diseases of man, domestic animals and fowls, known to be present in Panama, cause these ectoparasites to be of far greater importance from an economic and health standpoint in this locality than they would be in other regions having a more temperate climate and freedom from tick-borne diseases.