6 IOWA STUDIES IN NATURAL HISTORY 



he published the fii*st notice of the curious brachial articulation 

 now known as the syzygy. 



Sir Rawson Rawson had secured a number of comatulids at 

 Barbados, but the first published record for that island was 

 Pourtales' description of Antedon [Neocomatella] pidchella and 

 A. [N.] alata, which appeared in 1878. 



In 1912 Dr. Clemens Hartlaub's memoir on the comatulids 

 collected by the United States Coast Survey steamer "Blake" 

 was published, in which were listed a number of species from 

 twenty stations off Barbados. Isolated records of individual 

 specimens from Barbados appeared in 1912 and 1913. 



THE OCCURRENCE OP ISOCRINUS ASTERIA 

 AND OF HOLOPUS 



It is an extraordinary fact that in spite of all the dredging 

 that has been done in the Caribbean Sea and about the West 

 India Islands only four specimens of Isocriniis astena have been 

 brought up, one at Montserrat by the "Blake," one at Guade- 

 loupe by the "Blake", one off Saba by the "Investigator," and 

 a part of a stem off Havana by the ' ' Albatross, ' ' and only two of 

 Holopus rangii, one, a fragment, at Montserrat, and one off 

 Cuba, both by the "Blake." The majority of the known speci- 

 mens of both these species have been taken on fishermen's lines, 

 or by shore parties working from a small boat, or discovered on 

 the beaches. 



The apparent rarity of these species, in contrast to the other 

 species of Isocrinus, the species of Democrinus and the species of 

 Bythocrinus, is undoubtedly due to the fact that they inhabit 

 shallow water, living amongst the gorgonians and corals, like the 

 similarly rare West Indian astrophytons. 



This hypothesis is supported by the occasional occurrence of 

 Holopus rangii washed up on the windward beaches of Bar- 

 bados, where it is recorded also that once after a hurricane a 

 large number of individuals of Isocrinus of all ages and sizes 

 were cast ashore, and by the capture by Sir Rawson Rawson of 

 two specimens of Holopus in 5 fathoms of water. 



Speaking of the habitat of Isocrinus Sir Rawson wrote in a 

 letter to Dr. Gray: "I have only procured one specimen of the 



