SOLITARY CORALS. 199 



intervals as in that species, but only exhibits a succession of somewhat sinuous lines 

 of growth parallel to the curved margin of the calice. The three specimens differ 

 from one another in colour, in the characters of the lower edges of the septa, and of 

 the trabecular forming the parietal columella, but their resemblances are so great that 

 I must refer them to one species, viz., F. rubrwn, Quoy and Gaimard. 



Specimen a. Height, 12 milium ; calice, 15 millims. x 8 '5 millinis. ; scar, 

 G millims. x 35 millims.; depth of calice, 5 millinis. Angle formed by the directive 

 faces of the wall, 37. The dry corallum is white and has a small directive spine at 

 each end of the scar. The margin of the calice is entire, the directive ends of the 

 calice 2 millims. lower than the sides. There are eighty-two septa, whose character 

 and arrangement are shown hi fig. 4. The lower margins of the septa are furnished 

 with sharp spines, but are not sinuous ; the septal trabecular uniting to form the 

 columella are large and spiniform. The character of the trabecular columella 

 approximates this specimen to F. profundwn, M. Edw. and H., which is a variety of 

 F. rubvum. 



Specimen b. Height, 13 millims.; calice, 17 millinis. x 8*5 millims.; scar, 

 7 millims. x 3 5 millims. ; depth of calice, 4*5 millims. Angle formed by directive 

 faces of wall, 45. The dry corallum is of a brownish-grey colour and bears short 

 protothecal spines at either end of the scar. The calicular margin is crenulate, the 

 directive ends of the calice about 2 millims. lower than the sides. There are eighty 

 septa arranged in twenty apparent ternary systems. Eight of the tertiary septa are 

 equal in size to the primaries and secondaries and unite with them in the columella, 

 but four of the laterally placed tertiaries are of smaller size, and either barely reach, 

 or do not reach, the columella. The principal septa are thin, their inner margins 

 slope obliquely into the fossa, their lower edges are expanded and slightly sinuous 

 and terminate in nodular trabecular, which unite to form the columella. The septal 

 surfaces bear distinct radial ridges ornamented with spiniform granules. This 

 specimen is clearly identical with F. crenulatum, M. Edw. and H., which is a variety 

 of F. rubrum. 



Specimen c. Height, 13 millims.; calice, 15 millims. x 9 millims.; scar, 8'5 millims. 

 x 4 millinis. ; depth of calice, 5 millims. Angle formed by the directive faces of the 

 wall, 35. The wall in the dry corallum is of a deep reddish-brown colour, and the 

 same colour extends half way across the septa, a peculiarity which Semper 

 (49, p. 250, footnote) says is confined to F. pavoninum and F. distinctum. The 

 concentric lines of growth on the wall are distinct, the costar are scarcely recognisable, 

 and there are no protothecal spines. The calicular margin is entire, the directive 

 ends of the calice are about 1^ millims. below the lateral margins. There are 

 seventy-two septa, the tertiaries equal in size to the primaries and secondaries and 

 meeting them in the columella. The fifth cycle is complete in the terminal systems, 

 but incomplete in the lateral systems. The septa resemble those of specimen b, but 

 their inner edges are more vertical and their lower ends more decidedly sinuous. 



