IN the SIX years that have passed since the imhllcation of the 

 first number of this Catalogue, which treated of Oj^hiurida; 

 and Astrophytidie, our knowledge of these families has consider- 

 ably increased. Many new species have been discovered, among 

 which the singular forms, brought up by the deep-sea dredgings 

 off Florida, and described in Bulletin No. 10, Vol. I., are of par- 

 ticular interest. In the present Supplement to the Catalogue, 

 figures are given of the most important of these deep-sea 

 Ophiurans ; and there are added descriptions of one new genus 

 and of five new species from shallow Avater. There are given, 

 .also, lists of the principal authors, and of the new species de- 

 scribed by them, since 1865, making a continuation of similar 

 lists published in Catalogue No. I. 



LOUIS AGASSIZ. 



Oclolcr 10, 1 8 71. 



