Thomson, M.D., F.R.S., and to Messrs. Longmans & Co., Messrs. Cassell & Co., and Messrs. Kegan Paul & Co., for the use of various electros.

Dr. Murie, F.L.S., has had charge of many of the woodcuts, certain of which-representing ligaments, viscera, and salivary glands-have been drawn from his dissections and under his supervision.

I have to thank Mr. Alban Doran, who has made careful dissections of the internal ear and portions of the generative organs, and also Mr. P. Percival Whitcomb and my son Mr. Frederick St. G. Mivart, for more or less assistance. To Professor Cope I am much indebted for very kindly sending me proofs of unpublished plates of American fossils described and named by him.

I have also to express my obligation to Mr. Wm. Pearson (of the College of Surgeons) for making some excellent dissections, from which certain of the illustrations are taken. Original drawings have also been made from specimens preserved in the museum of the Royal College of Surgeons and in the British Museum. The drawings have (with the exception of six figures of fossil remains) been executed by Mr. C. Berjeau and engraved by Mr. Ferrier. I feel bound to express my sense of the skill evinced in their execution.