REPORT ON CORALS — DEEP-SEA MADREPORARIA. 171 



series of transverse curved accretion stria?. The six angles are the primary costse, the 

 secondary costse are just marked as faint narrow ridges between them. The young corals 

 are perfectly symmetrical, the hexagonal mouth of the ealicle is slightly elongate, the 

 two lateral of the six sides being slightly broader than the four end ones. There are 

 twelve septa. The six primary meet the small oval columella at the base of the fossa 

 and ealicle with their inner margins ; the six secondary are incomplete and are not 

 continued quite down to the bottom of the ealicle. The base of the ealicle is attached 

 by a smooth, glistening, terminal surface of coral matter, the under surface of a thin, 

 horizontal lamina which forms the bottom of the ealicle. In this lamina can be plainly 

 seen embedded the bottoms of the six primary septa symmetrically arranged, and 

 without any secondaries, showing that six septa symmetrically disposed were originally 

 developed first in the young corallum. The outline of the bottom of the ealicle is 

 not hexagonal, but bounded by four nearly equal curves, one at each end and two 

 lateral. The hexagonal form is gradually assumed higher up. The margin of the 

 ealicle is already dentate in the young coral, larger dentations corresponding with 

 the primary septa and minute ones between them answering to the secondaries being- 

 present. 



Two of the adult specimens obtained were alive, and expanded themselves when 

 placed in sea-water, notwithstanding the depth from which they came. The inner 

 margin of the disk around the elongate mouth presents a regular series of dentations 

 corresponding with the septa, and is of a dark madder colour ; the remainder of the 

 disk is of a pale pink. The tentacles take origin directly from the septa ; they are of 

 an elongate conical form ; those of the primary and secondary septa are equal in size, 

 and placed nearest the mouth, and at equal distances from it, together with the 

 tertiary tentacles, which are somewhat shorter, but are placed in the same row with 

 them. The tentacles of the fourth and fifth cycles are successively smaller, and placed 

 at successively longer distances from the mouth. Placed on either side of each tentacle 

 of the fifth cycle, and again somewhat nearer to the margin of the ealicle, are a pair of 

 very small tentacles which have no septa developed in correspondence with them. 

 The number of tentacles is thus ninety-six. The tentacles are light red in colour. 

 Between their bases are stripes of yellowish-red and pale-greyish. For some account 

 of the anatomy of this species, see the Introduction, p. 130, and also pp. 163, 164 of 

 the present memoir. 



Measurements of an adult specimen : extreme height of the ealicle, 50 mm. ; 

 longer diameter of the ealicle, 65 mm. ; shorter diameter, 30 mm. 



Young specimens : height of the ealicle, 5 mm. ; longer diameter of the ealicle, 

 4 mm. 



Stations 73 and 78, off the Azores, from 1000 fathoms. Five adult specimens, three 

 living and two dead and fragmentary, and two very young specimens. 



