182 THE VOYAGE OF H.M.S. CHALLENGER. 



Family Stylophoeid.e, Pourtales. 



Madracis. 



Madracis asperula, Milne-Edwards and Haime (Hist. Nat. des Corails, t. ii. p. 139). 

 Very large quantities of this coral were brought up by the swabs from 30 fathoms, off 

 Bermuda. The bottom was evidently covered thickly with the coral. 

 On the South-west Bank, Bermuda. 30 fathoms. 

 Off the shore of Fernando de Noronha, in shallow water. 

 At St Vincent, Cape Verde Islands. Shallow water. 



Axohelia. 



Axohelia dumetosa, Duch. 



One specimen obtained is identical with one named by Count Pourtales, and agrees 

 also with his descriptions and figures. He retains the genus Axohelia apart from 

 Madracis for the species with compact ccenenchyma. 1 



Station 33, off Bermuda. 435 fathoms. 



Family Astr^eidje, Dana. 

 Sphenophyllia, u. gen. 



Corallum solitary, free, pedicellate, compressed, with septa finely denticulate at the 

 summits, and numerous sharp-edged costas which are denticulate, rendering the corallum 

 exceedingly rough. A scanty epitheca at the base ; no endotheca or exotheca ; a well- 

 developed lamellar columella. 



The genus is allied to Antillia (Duncan), 2 but differs in having no endotheca or 

 exotheca, and differs from Tmchyphyllia, to which it has also affinities, in being solitary. 



Sphenophyllia flabelhtm, n. sp. (PI. X. figs. 1, la, lb). 



The corallum is white, extremely compressed, conical and deltoid in form. The 

 summits of the short axis are higher than those of the long axis ; and the lateral margins 

 of the calicle are evenly curved, sometimes a little undulating. There is a distinct 

 pedicle, with trace of attachment. Around the pedicle, and for a short distance above it, 

 there is a scanty opaque epitheca. The surface is roughened all over by sharp-edged 

 costal ridges, which converge from the calicular margin towards the pedicle all round. 

 These costte correspond to the major septa ; they are sharp-edged and finely dentate 

 throughout their extent, so that the outer surface of the coral is extremely rough. 



1 Pourtales, " Hassler " Expedition, p. 40. 



2 West Indian Corals, Proc. Geol. Soc, Nov. 1863, p. 28. 



