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CONTRIBUTIONS FROM THE BERMUDA BIOLOGICAL STATION 



FOR RESEARCH. No. 138. 



THE ECHINODERMS OF THE CHALLENGER BANK, 



BERMUDA. 



By Hubert Lyman Clark. 



Presented by E. L. Mark. Repeived April 8, 1922. 



When H. M. S. Challenger visited Bermuda in 1873, one day 

 (April 23) was spent in "sounding out" the "bank" lying a few miles 

 southwest of the Bermuda bank itself, and as a result this shoal area, 

 some seven miles long and six miles wide, with a minimum depth of 

 24 fms. has since been known as the Challenger Bank. In August, 

 1903, a party from the Bermuda Biological Station, under the direction 

 of Professor E. L. Mark and Professor C. L. Bristol, made an excursion 

 to the Bank and did some dredging there.-^ One of the party, Dr. 

 H. B. Bigelow, has published (1905, Proc. Amer. Acad. 40, pp. 586- 

 591) a very interesting account of the physical characteristics of the 

 Bank, and of the peculiar nodules with which it is covered. So far 

 as I can learn, no other scientists have done any dredging on the 

 Challenger Bank and our knowledge of its fauna must thus be based 

 on the material obtained by these parties in 1873 and 1903. The 

 Challenger took but four species of echinoderms, one sea-star 

 {Chaetasfer nodosiis, recorded in the Challenger Reports as Ch. 

 longipes) and three brittle-stars {Ophiomi/xa flaccida, Ophiofhrix angu- 

 lata, Ophiothrix suenso)iii). The party from the Biological Station did 

 much better, as they dredged a dozen species. This collection lias, 

 through the kindness of Dr. Mark, recently come into the possession 

 of the IVIuseum of Comparative Zoology and as it proves to be of 

 unusual interest, the present report has been prepared. 



Of the four species taken by the Challenger, the party from the 

 Bermuda Biological Station took all except Ophiomyxa flaccida, a 



1 This expedition was made possible by the invitation of the late Captain 

 William E. Meyer, ship owner, of "Gliickauf", St. Georges, Bermuda, who 

 very generously fitted out his ocean-going tug Gladisfen for the occasion, 

 and with her crew personally took the whole membership of the Biological 

 Station, thirty-seven in number, and a few^ others for a three days' trip to the 

 Challenger Bank. The expedition left St. Georges on July Slst, 1903, and 

 returned on August 2nd. E. L. Mark. 



