The number of drugs which dilate the pupil is so very large, and the physiologic relations of many of them so distant, that a consideration of all those substances which might be called mydriatics would not only consume much more time than is at our disposal, but would necessitate classing together of drugs not naturally so related. I shall, therefore, confine my remarks to those alkaloids which belong to the series of tropins; and for similar reasons of brevity omit the consideration of the synthetic alkaloids of this series, such as homatropin.
Before, however, taking up the consideration of the physiologic action of these substances, I wish to call attention to the very unfortunate confusion in the nomenclature of the active principles of the solanaceous plants. As various investigators have from time to time discovered in different members of this family alkaloidal principles, they have given new names to their