436 PROF. P. M. DUNCAN ON DEEP-SEA [May 16, 



As the form has no endotheca, is simple, and without pali, it 

 comes within the Turbinolinse, in the neighbourhood of Desmo- 

 phyllum, Smilotrochits, and Discotrochus ; but it differs from all. 



Like the two well-known Japanese simple corals, the corallum 

 has its base surrounding a shell ; but in this instance the small 

 Difntpa-Wke annelid does not always interfere with the symmetry of 

 the base. 



Genus Brachytrochus. 



The corallum is very short, free, or incrusting annelid-shells. 

 The calice is circular, and deep centrally; there is no columella. 

 The septa are exsert and papillose ; the costse are well developed, 

 except on the rounded centre of the base, where they merge into a 

 granular structure. 



Brachytrochus simplex, sp. n. (Plate XXXIX. figs. 7-10.) 



The calice is widely open, and the floor of the fossa is visible. 

 The septa are in six systems, and there are four perfect cycles in 

 each ; the primaries are the largest, the most exsert, and project 

 the most internally and externally ; the secondaries are slightly 

 smaller than the primaries, and larger than those of the third order. 

 The fourth and fifth orders are the smallest, and rather approach 

 the tertiaries. 



All have large and wide papillae internally ; and those of the third 

 and higher orders of septa reach furthest from the axis. The septa 

 are rounded faintly and are thin and exsert. 



The costse are profusely granular. The inner granulations, or 

 papillae of the septa, radiate, as it were, from where the columella 

 might have been. 



Height t^ inch. Breadth T 4 inch. 



Locality. Gaspar Straits, 12 fathoms. From the Liverpool 

 Museum. 



Family Oculinid^e, Ed. & H. 



Oculina cubaensis, sp. ii. (Plate XL. figs. 1, 2.) 



The corallum incrusts dead Polyzoa and Serpulce, and rises also in 

 the form of irregular stems which branch and often coalesce. Gem- 

 mation sometimes lateral and alternate, at other times in spiral 

 series, and without order. 



The calices are not very prominent, and are moderately deep. The 

 columella is extremely small and trabecular ; the septa are alternately 

 large and small ; and the primaries and secondaries are exsert, arched, 

 and finely spinulose at their margin. There are rarely three com- 

 plete cycles. The pali are before all the septa except the last, are 

 long, rather papillose at the surface, tall, and their inner end meets 

 the almost rudimentary columella. The costse are often well seen 

 over the sides and running between the corallites ; at other times 

 they are wanting. They are often unequal, a large one being fol- 

 lowed by a very small one. All are minutely granular, so that they 

 feel as if spiny. 



Fissiparity is rare. 



