100 SMITHSONIAN INSTITUTION 



CLASSIFICATION 



In the North American Crinoidea Camerata by Wachsmuth and myself, 1 

 there was given a historical resume of the principal writings upon the crinoids, 

 and a discussion of the various plans of classification put forth from time to 

 time by different authors. It is not my purpose in the present treatise to re- 

 trace the steps there taken, nor to deal with those subjects anew, except to 

 supply some matters not sufficiently covered before, and to bring the question 

 of classification down to date in the light of researches and publications since 

 the appearance of that work. 



In the history of opinion as to the nature and relations of the crinoids 

 sufficient credit was not given by us to the pioneer work of Edward Llhuyd 

 (Luidius), Head Keeper of the Ashmolean Museum at Oxford, 2 who was the 

 first author to notice the intimate relationship between the fossil Crinoidea and 

 the living comatulid now known -as Anted on bifida. This he did, as W. B. 

 Carpenter has justly said, " not as a mere guess, but on the sound basis of 

 anatomical correspondence," with an accuracy and discrimination which stamps 

 him as an observer and thinker far in advance of his contemporaries. 



Of the classifications of the Crinoidea into large, divisions the two which 

 have had the greatest influence upon the knowledge of this group of Echino- 

 derma are undoubtedly those of J. S. Miller 3 and Johannes Midler. 4 



Miller's classification is important first of all because he was the earliest 

 author who undertook to treat in a systematic way the Crinoidea as a class. 

 This class was limited by him to the stalked, brachiate crinoids, thus excluding 

 from consideration forms now known as cystids and blastoids which he did not 

 discuss at all, and Marsupites and the Comatulae which he placed among the 

 " Stelleridae." The comatulids, which, since J. V. Thompson's epoch-making 

 discovery of the young in 1827, and of the connection between the young and 

 the adult in 1835, have been known to be stalked in their young or " pentacri- 

 noid " stage, were logically included in his definition, and are so treated by all 

 modern authorities; Miller himself noted their resemblance to the crown of 

 Pentacrinus, and called attention to the fact that the plate at the base of the 

 calyx of the Comatulae occupies the same position as the first columnal of the 

 Crinoidea. 



1 Mem. Mus. Comp. Zoology, Harvard, vol. 20, 1897, pp. n-31, 144-161. 



* Lithophylacci Britannici Ichnographia, 1699, pp. 44, 101 ; Edition 1760, p. 145. ■- 



3 A Natural History of the Crinoidea, 1821. 



*Bau des Pentacrinus caput-medusae, Monatsber. Akad. Wiss. Berlin, Apr. 1840, pp. 88-106; Wieg- 

 mann's Archiv., 1840, pp. 307-318; Abhandl. Konigl. Akad. Wiss. for 1841, pub. 1843, pp. 177-248; separate, 

 pp. 1-72. 



