﻿IV PREFATORY NOTE. 



and resources permitting, it is next in order to take up the investigation of genera 

 and species from the structural point of view; for now that the more obvious 

 boundaries and botanical aspects of the group have been determined, the logical 

 order of subsequent study of the cycads clearly is to determine the taxonomy and 

 coordinate such labor with field exploration. Amongst special features promising 

 much further biologic interest the cycad seeds may well be mentioned. So far as 

 the present work is concerned, however, it is felt that if any portion of it is to 

 endure, it must more likely be the plates, in so far as they are not destined to be 

 supplanted, in the course of time, by the photographs of larger, better cut, and 

 handsomer sections. 



Amongst those who, subsequent to Professor Marsh, have furthered these inves- 

 tigations, I desire to mention the following: To the late Professor C. E. Beecher, 

 and to Mr. J. F. Maloue, of New Haven, and especially to Professor Charles S. 

 Hastings, I am much indebted for help in and explanation of the methods of 

 photomicrography. The opportunity to secure various of the habitus illustrations, 

 which have added much to the value of the ninth chapter, is due to Mr. Ferdinand 

 Mangold, of Tarrytown, New York ; while Mr. George C. Pope, of Brooklyn, New 

 York, furnished from his conservatory the photographic text figures 8 and 9. Much 

 has been added by the skill and painstaking attention to detail given by Mr. G. S. 

 Barkentin to the brush drawings and to the ink work on the text figures, as chiefly 

 done by him. To Professor Ikeno, the discoverer of antherozoids in the cycads, 

 students of botany will be particularly grateful for having made the journey to the 

 Ryugeji Temple gardens, resulting in the unique plate-figure facing page 21. The 

 permission of Professor Thomas H. Macbride, of the State University of Iowa, to 

 section the splendid bisporangiate strobilus illustrated on the frontispiece, and 

 plates xxxiv and xxxv, was especially considerate, the more so as coming at 

 a time when the old prejudices against cutting certain trunks still lingered in 

 places. To the courtesy of the late Professor Wilbur C. Knight of the State Uni- 

 versity of Wyoming at Laramie, I am similarly indebted for much material illus- 

 trating the genus Cycadella, although time has not yet permitted an adequate 

 examination of all these specimens. 



I wish especially to express my gratitude to Professor Lester F. Ward, not 

 only for important material for study, but for many valuable suggestions and favors 

 extending over the past eight years, and for taking the great trouble to read the 

 proof of most of the chapters. 



Above all I desire to here record my deep obligation to Professor Othniel 

 Charles Marsh: With a keen and unerring appreciation of scientific values he 

 furthered the field explorations which finally resulted in the great cycad collections 

 now in the Yale Museum, and with an equally great and kindly interest, devotedly 

 extending to life's last hour, he encouraged their laboratory study. 



To the Carnegie Institution, and to the constant and laborious care of its 

 officials, Science is indebted for the assemblage of these results in the costly and 

 elegant form in which they are illustrated and presented in this volume. 



G. R. WlELAND. 



Yale University, New Haven, Conn. 



