Report on the Crinoidea and Echinoidea 



Collected by the Bahama Expedition 

 from the University of Iowa in 1893 



By Hubert Lyman Clark, Ph. D. 



Museum of Comparative Zoology, Cambridge 



Early in March, 1916, the collections of crinoids and sea- 

 urchins made by the University of Iowa's Bahama Expedition 

 in 1893 were placed in my hands for study and identification. 

 No collection of holothurians was made by the Expedition, while 

 the sea-stars and brittle-stars have been reported on by Professor 

 A. E. Yerrill (Nat. Hist. Bull., V, 1 and VII, 1). To complete the 

 account of the Echinodermata, therefore, it is desirable that a 

 report be made on the collections turned over to me. While there 

 is no close relationship between the crinoids and echinoids 

 (indeed they represent quite different lines of evolution from a 

 presumably Cystid stock), it is most convenient to embody my 

 notes on the two groups in a single report. For the honor 

 done me, in placing this interesting material in my hands, as 

 well as for his help by correspondence, I vdsh to offer my sin- 

 cere thanks to the leader of the Bahama Expedition of 1893, 

 Professor C. C. Nutting. 



It is to be regretted that the crinoids and echini Avere not 

 studied soon after they were collected, for during the past 

 twenty years much has been published on these groups as found 

 in the West Indian region. There is not, therefore, any now 

 undescribed species in the series before me tliough there are 

 probably five crinoids and one sea-urchin which were new to 

 science when taken. The chief value of the collections now lies 

 in the large series of young echini, which throw much light on 

 the grovv'th stages of several little known species, and in the 

 data provided on the distribution of the species represented. 

 The notes on the Echinoderms taken at the various stations, pub- 

 lished in Professor Nutting's "Narrative" of the Expedition 

 (1895, Bull. Univ. Iowa, Lab. Nat. Hist., vol. 3. iios. 1 and 2) 

 are not only of great general interest but are of much scientific 



