sion belonged to the genera Solenosmilia, Lophohelia, Desmophyllum, and 

 Caryophyllia. 



The Andaman Sea ought to be a good place for corals, but it has not yet 

 been sufficiently explored : so far, we have only got six or seven species from 

 it, and but few specimens of those. 



Off the Cororaandel coast, in the Bay of Bengal, at a depth of about 600 

 fathoms, where the bottom -mud begins to harden to a stiffish clay, we have 

 constantly found, in goodly number, Flabellum japonicum Moseley, Flabellum 

 laciniatum Philippi, and Bathyactis ; but besides these only two other species, 

 namely a Caryophyllia and a Rhizotrochus, have been dredged. 



II. THE GEOGRAPHICAL DISTRIBUTION OF CERTAIN 

 INDIAN DEEP-SEA CORALS. 



Of the 25 species described in this paper 19 are believed to be peculiar 

 to the depths of the seas of India, although three or even four of them have 

 a most suggestive resemblance to certain fossil forms described and figured by 

 Seguenza from the Sicilian Tertiaries. 



The remaining six species, which are not peculiar to India, are Caryo- 

 phyllia communis, Acanthocyathus grayi, Flabellum laciniatum, Flabellum 

 japonicum, Bathyactis symmetrica, and Cyathohelia axillaris. 



Of Acanthocyathus grayi I can find no other notice than that of its 

 authors, Milne Edwards and Haime, who state that its habitat is unknown. 



Of the rest, Bathyactis symmetrica is known to have a world-wide distri- 

 bution, and Flabellum japonicum and Cyathohelia axillaris are two of the 

 many marine forms that are common to India and Japan. 



The remaining two Caryophyllia communis and Flabellum laciniatum 

 may also be taken as furnishing instances of the wide range that a good many 

 deep-sea forms are known to have. But as they are Atlantic species, and are 

 also known as fossils from the Tertiary Deposits of Sicily and Calabria, I think 

 it equally probable that they give confirmatory evidence of the former open 

 sea connexion between the Atlantic and Indian Oceans, by way of the Medi- 

 terranean, that geologists believe to have existed in early Tertiary times. As 

 this is a bold theory for such slender zoological evidence to support, I must 

 take this opportunity of offering some further corroborative evidence, obtained 

 by summarizing the knowledge acquired by the " Investigator " of the fauna 

 of the Indian Seas at the depths at and near which Flabellum laciniatum and 

 Caryophyllia communis occur. 



Excluding the Foraminifera (of which there are about 280 species) the 

 total number of named deep-sea Metazoa in the " Investigator" collections is 



