32 IOWA STUDIES IN NATURAL HISTORY 



essentially similar to the Brazilian, minus certain types and plus 

 a few others. The most conspicuous of the latter is the littoral 

 Thyraster serpentarius, but this is known only from Vera Cruz 

 and from off Tampa Bay, Florida (Cat. No. 36995 U. S. National 

 Museum ) . 



The third division, which appears to be merely the preceding 

 minus a number of its characteristic types and plus a few which 

 possibly are not in reality confined to it, includes the Antillean 

 Islands north of Tobago and the Atlantic coast of North America 

 to Carolina, some of the species even reaching Cape Cod. This 

 division is richest in species in the Greater Antilles and southern 

 Florida, and poorest in the southern Lesser Antilles, especially 

 on the oceanic island of Barbados. 



THE OPHIURANS COLLECTED BY THE EXPEDITION 



The expedition brought back representatives of forty-three spe- 

 cies of ophiurans; of these 26 were found at Barbados only, 14 

 were found both at Barbados and at Antigua, and 3 were found 

 only at Antigua. 



Of the 40 species collected at Barbados the following 11 were 

 there found for the first time : 



Ophiomyxa flaccida Amphiodia planispina 



Astrophytum muricatum Ophiactis savignyi 



Ophioplits tuherculosus Ophiothrix lineata 



Amphmra diducta Ophiothrix pallida 



Amphipholis limhata Ophiomusium scidptum 



Ophiolepis elegatis 



The 17 species collected at Antigua constitute new records; 

 they were : 



Ophiomyxa flaccida Ophiocoma riisei 



Ophiactis tnidleri Ophioderma appressa 



Ophiothrix angulata Ophioderma brevicauda 



Ophiothrix oerstedii Ophioderma cinerea 



Ophiothrix suensonii Ophioderma ruhiciinda 



Ophionereis reticidata Ophiura acervata 



Ophiocoma echinata Ophiomusium validum 



Ophiocoma pumila Ophiolepis elegans 

 Ophiolepis paucispina 



