LECTURES colding ON HISTOLOGY, DELIVERED AT THE ROYAL COLLEGE OF SURGEONS OF ENGLAND, IN THE SESSION 1851-52. BY JOHN WRETTY RESIDENT CONSERVATOR OF THE MUSEUM OF THE ROYAL COLLEGE OF SURGEONS AND PROFESSOR OF HISTOLOGY. ORK HOSPIT VOL. II. STRUCTURE OF THE SKELETON OF PLANTS AND ILLUSTRATED BY TWO HUNDRED AND SIXTY-FOUR WOODCUTS LONDON: LANE MEDICAL LIBRARY 15893 HIPPOLYTE BAILLIERE, 219, REGENT STREET, AND 290, BROADWAY, NEW YORK, U.S. PARIS: J. B. BAILLIERE, RUE HAUTEFEUILLE. MADRID: BAILLY BAILLIERE, CALLE DEL PRINCIPE. 1854. 273 23 1854 V. 2 PREFACE. So favourable a reception having been given to the First Volume of these Lectures, the Author is induced to bring a Second before the Public, and he hopes it will be found both instructive and interesting. The minute structure of the Skeleton of Plants and Invertebrate Animals is a study of the greatest interest, and one which will fully repay the most careful investigation. To the Zoologist, the Geologist, and even to the Amateur in Microscopic Science, a knowledge of this subject must prove of the highest value, not only on account of the great variety of beautiful structures embraced by it, but from the wellmarked characters that each part of the skeleton presents-characters not wholly obliterated even in the fossil state, and by which alone the smallest fragments of particular structures can be satisfactorily recognised. The great demand for information on Histological subjects is made evident, not only by the large number of first-rate instruments now being manufactured, but also by the fact that several skilful artists are entirely employed in the preparation of microscopic objects, many thousands of which are annually sold in this metropolis. In publishing these Lectures, the Author is most anxious to point out that collections of specimens are not only valuable for their beauty or their peculiarity of struc |