INTRODUCTION 1 5 



than had been found by all previous collectors during 50 years, forming an 

 assemblage of crinoids which will take rank with the great collections from the 

 equivalent horizon in the Island of Gotland, and which exhibits in some respects 

 a remarkable parallelism with the Gotland fauna. Afterward Mr. Pate spent 

 a considerable part of two more seasons in the Linden beds of Hardin and 

 adjacent counties in Tennessee, with extraordinary results in the way of new 

 material to which my memoir on the genus Scyphocrinus bears witness. Mr. 

 Pate knows the geology of Kentucky and Tennessee most intimately, and when 

 in the field collects with amazing energy, and with an intimate knowledge of the 

 stratigraphy. 



During the past three seasons my assistant, Dr. Herrick E. Wilson, has 

 made important collections in the Laurel limestone at St. Paul, Indiana, and 

 vicinity, the crinoid fauna of which bears a striking resemblance to that of a 

 part of the Wenlock of Gotland. Dr. Wilson has also made the microscopic 

 studies and the drawings upon the remarkable series of comatulid larvae de- 

 scribed and figured in this work. 



Illustrations 



I have been peculiarly favored in the preparation of the drawings for the 

 accompanying plates by having the services of two of the most skillful living 

 artists in this line of work. Mr. LiljevalFs share in their execution has already 

 been stated. Mr. Kenneth M. Chapman, now of Santa Fe, N;ew Mexico, began 

 making drawings for me in 1900, and has continued to do so ever since. He 

 was then without experience in that class of work; but his technical skill, fine 

 artistic sense, and keen scientific observation of details enabled him to keep 

 pace with my requirements until he became the master to whose preeminence 

 the 75 beautiful plates of this work, as well as the numerous others in previous 

 publications, bear convincing testimony. His unflagging interest in the prepa- 

 ration of these volumes has made our association one of continual pleasure. 

 Mr. Chapman in addition to the pencil wields a skillful brush, as his canvasses 

 in oil show, and his original studies upon the evolution of Decorative Art have 

 made him one of the leading authorities in that branch of archaeological 

 research. 



Mrs. Edith Ricker, of Burlington, Iowa, made some drawings for this 

 work at its beginning, and the fine figure 3 on Plate LXXII stands as proof of 

 her skill. I am also indebted to Professor Maurice Ricker for helpful assist- 

 ance in photography at that time. 



All of my plate figures, except the drawings of comatulid larvae, are made 

 from a photographic basis, but they are not in any sense mere retouched photo- 

 graphs. A very light print is made upon a paper which will take water color, 

 giving the outline and sutural details which formerly constituted the drudgery 



