The author of this work has long been known as one of the most expert microscopists in the country, and his mounted specimens have been much admired by all who have had the good fortune to see them. In the production of this little volume the author has turned his long practical experience to good account. He has succeeded in condensing in a minimum space a great deal of material of especial interest to the practitioner. The success of the distinguished author shows that the general practitioner need not despair of becoming a microscopist, if like the author. he will industriously and patiently work out the problem for himself and this book if carefully studied will help to show him how to do it.