Originally published in 1915, It's object is to afford a general survey of the field, and primarily to put the student of medicine and entomology in touch with the discoveries and theories which underlie some of the most important modern work in preventative medicine. At the same time the older phases of the subject - the consideration of poisonous and parasitic forms - have not been ignored. The information on Entomology makes for absorbing reading throughout with much of it still being useful and practical today. Many of the earliest books, particularly those dating back to the 1900's and before, are now extremely scarce and increasingly expensive. We are republishing these classic works in affordable, high quality, modern editions, using the original text and artwork.