26 



exsert than the others and divide the calice into 2 1 compartments ; of these 2 1 compartments 

 16 contain three smaller septa each, and 5 contain only one smaller septum. 



The 21 large exsert septa merge with the columella, but just before they do so they 

 are notched, so that at their junction with the columella there is a sort of low paliform 

 thickening — sinuous and very indistinctly paliform. 



Of the 53 smaller septa, the middle one in each group of three gives off, very low down 

 in the calicle, a bold paliform lobe, and then either runs on to the columella or joins one of 

 the larger septa; while the remaining 37, which are narrow, end on the wall of the calicle. 



The columella, which though low is ver)- large and singularly compact, is made up 

 almost entirely of the thickened granular contorted impacted ends of the 2 1 large septa, with 

 but little assistance from the 16 septa of the next degree. 



Greatest height of corallum to the summit of the most exsert septa about 25 millim. 

 Diameter of calicle „ 2>7 » 



Stephanotrochus sp. 



Stat. 173. 3° 27' S., 131° o'.5 E. 567 m. 1 Ex. 

 Stat. 284. 8°43'.i S., i27°i6'.7E. 828 m. i Ex. 



I do not number these specimens, as I believe them to be only dead and broken 

 coralla of S. zoeberianus. Though they are shallower than the type specimen they have the 

 same number (twelve) of large septa, and the same bulge or thickening where the sidewall 

 joins the base of the corallum. 



XV. Sabinotrochus Duncan. 



Sabinotroclnis Duncan, Transactions of the Zoological Society of London, VIII, 1874, p. 320 

 (1871), and Journal of the Linnean Society, Zoology, XVIII, 1885, p. 29. 



Two small dead coralla, which I was at first inclined to refer to FlabcIliDU, near 

 F. angulare Moseley, seem to be, perhaps, referable to this genus. 



31. } Sabinotrochus flatiliscpiis n. sp. Plate IV. Fig. 24, 24a. 



Stat. 211. 5°4o'.7S., i20°45'.5 E. 1158m. i Ex. 



Corallum saucer-shaped, with a pedicled scar of attachment, whence radiate costce, 

 which, as well as the furrows between them, are covered with "oolitic" granules. 



Septa in six systems and three cycles with some traces of a fourth. Those of the first 

 two cycles are large and are remarkably inflated and granular in the middle of the shallow 

 calicle, where they meet to form an umbilicated columella. Those of the third cycle sometimes 

 join those of the second, but more often they end about midway between the centre and the 

 circumference of the calicle. 



Height of corallum about 5 millim. 

 Diameter of calicle 1 1 „ 



