A REVISION OF THE GENUS STEGANOPORELLA. 255 



species has a wide distribution, but the specimen in question 

 more closely coi-responds with those from the West Indies 

 and Abrolhos I. (coast of Brazil) than with any others I have 

 seen. A slide in the Busk collection at the British Museum 

 (referred to on page 176 of the ^'Challenger Eeport/' 

 part xxx) is labelled " John Adams' Bank, North Atlantic," 

 as I am informed by Mr. Kirkpatrick ; while the Bank is 

 said to be in the South Atlantic on page 36 of Part III of 

 the British Museum Catalogue of Polyzoa. I am indebted 

 to Mr, Kirkpatrick, to Captain Tizard of the Hydrographic 

 Department at the Admiralty, and to Captain Froud of the 

 Shipmasters' Society, for much trouble which they have 

 taken in trying to elucidate this point. Although there is 

 an Adams Rock at Pitcairn Island, I am satisfied, as the 

 result of a letter received from Captain Craig, of the U.S. 

 Hydrographic Office, that the Bank is identical with the 

 '^ Victoria Bank " (S. of Abrolhos I.) of our own Admiralty 

 charts. The discovery of this Bank by the U.S.S. "John 

 Adams" is announced in the 'Nautical Magazine,' 1850, 

 p. 186, and Captain Craig informs me that the name ''John 

 Adams Bank" is still employed in a publication^ of the 

 " Service Hydrographique de la Marine " at Paris. 



The species appears to be a well-marked one, the connection 

 of the lateral walls of the median process with the sides of the 

 zooecia (fig*. 6), and the consequent formation of two distinct 

 " opesiules " on each side, being- particularly noteworthy. 

 The species has a robust appearance. The epitheca and the 

 opercula are thick and strong, and the calcareous parts a-re 

 no less strongly developed. 



The edge is but slightly raised, and is separated by a slight 

 groove from the post-oral shelf. This is massive, deep, and 

 coarsely tubercular, being strongly developed even proximally, 

 where the shelf is narrow in several of the other species. 

 The oral shelf is narrow and smooth. The condyles are 



' ' Instructions Nautiques . . . Bresil,' by Mochez and Roqueniaurel, 

 1890. 



