REPORT ON CORALS— DEEP-SEA MADREPORARIA. 147 



variety of Deltocyathus agassizi cannot be upheld. Sabinotrochus differs in its general 

 texture, and in the thickness of its septa, in its fine wavy costse, and in the margin of its 

 calicle being indented, also in the complete absence of pali, which are certainly not 

 broken away. In all my specimens of Deltocyathus italicus there are pali, or remnants of 

 them. Sabinotrochus seems rather nearly allied to Stcphanotrochus. After decalcifica- 

 tion of specimens of this species hardened in absolute alcohol, an external film of soft 

 tissue separates from the outer surface of the wall, but only from that region of it 

 near the mouth of the calicle ; all the region near the tip of the cone is devoid entirely 

 of living tissue. 



One specimen of a coral, which is in a semifossilised condition, embedded partially in 

 a hard black clay, and much decomposed, appears referable to Deltocyathus agassizi. If 

 so, it is of remarkably large size, measuring 18 mm. in diameter. 



Station 78, off the Azores. 1000 fathoms. Fifty specimens. 



Station 56, off Bermuda. 1075 fathoms. Several specimens. 



Station 120, off Pernambuco, Brazil. 675 fathoms. 



Station 24, off Culebra Island, Danish West Indies. 390 fathoms. 



Station 285. Attached variety. One specimen. South Pacific Ocean. Lat. 32° 36' 

 S., long. 137° 43' W. 2375 fathoms. 



Off Bermuda. 200 fathoms. Var. calcar. One specimen only brought up in a 

 sounding machine. 



Station 191, between the Aru and Ki Islands. 800 fathoms. Very large dead 

 specimen of this species (?). 



Deltocyathus magnificits, Moseley (PI. IV. fig. 10, PL XIII. figs. 1, 2). 

 Deltocyatlius magnificus, Moseley, Proc. Roy. Soc, 1876, p. 662. 



In this gigantic species of the genus the corallum is quite flattened and discoid. 

 The inferior surface is slightly concave, the margin of the calicle being somewhat tumid 

 owing to the prominence of the costse. The tissue composing the corallum is dense, and 

 of a slight reddish-yellow not white as in Deltocyathus agassizi. On the under surface the 

 wall is smooth, but shows a few concentric rings of growth and a slight conical elevation in 

 the centre which points to the coral having been cup-shaped in the very young condition. 

 The costse are all nearly equally developed ; they commence in succession in the centre of 

 the inferior surface or near to it as fine lines composed of very minute granules, and begin 

 to rise from the surface as fine projecting laminae only towards the outer half of the 

 surface ; towards the margin they are very prominent with rounded ridges, and being all 

 of equal prominence give the margin a tumid appearance. On close inspection the 

 primary and secondary costal laminae can be seen to be slightly thicker than the tertiary 

 quaternary and quinary which are closely alike. There are six systems and five complete 



