NOUR. 
THE Manuscript of this work in its present form was received at Cam- 
bridge for publication September 1, 1894. Although in press ever since 
then, no part of it has been published until now, and the date of the work, 
for bibliographic purposes, will be that which appears on the title-page. 
During the long time that has been consumed in the printing of the plates 
and letter-press work since the completion of the text, many new species 
of Crinoids have been described by American authors, among which some 
of those herein mentioned as new are included, and thus anticipated. No 
attempt has been made to cover these cases by modifying the text, nor 
have any questions arising upon publications appearing subsequent to the 
above date been considered here. In a work of this size while in press 
changes could not be made to keep pace with current researches, and the 
date of delivery of the Manuscript for publication was therefore taken by 
the authors as final, so far as they were concerned. 
It is a source of extreme regret that my learned colleague and long-time 
friend, Dr. Charles Wachsmuth, did not live to see the publication of this 
Monograph, to which he had devoted so many years of assiduous labor. 
Never a robust or healthy man, his last few years were almost a continual 
struggle against disease. His strength gradually failed, and he passed away 
on February 7, 1896, at the age of sixty-seven years. 
Dr. Wachsmuth was a native of Hanover, Germany. He came to the 
United States in 1852, and soon after engaged in mercantile pursuits at 
Burlington, Iowa, which became his permanent home. Failing health in 
time compelled him to relinquish business, and for the last thirty years he 
applied himself to the study of the Crinoids, first as a recreation and to 
secure outdoor exercise, and afterwards as his life work, with all the ardor 
of a scientific devotee. His keen powers of observation, sagacious judgment, 
and indefatigable energy have left their impress upon the works which have 
been brought out by us. While his death is a loss to Science not easily 
repaired, it is to none so great—aside from his family — as to the friend 
with whom he had worked in pleasant collaboration for so many years. It 
is with a melancholy pleasure that I avail myself of the opportunity afforded 
by the appearance of his last work to pay this slight tribute to his memory. 
FRANK SPRINGER. 
Las Vegas, New Mexico, 1897. 
