900 



MISS K. M. UAKIILSOX AND MISS M. POOLE ON [DeC, 14, 



from 2 to 10 mm. below the sides, and the latter may be straight, 

 convex, or slightly concave. The coi'allum is completely covered 

 by an epitheca marked by slight vertical ridges and horizontal 

 concentric lines of growth. There is almost always a root-like 

 process at either end of the basal scar, and often one or two pairs 

 nearer the calice. The septa, which are somewhat exsert round 

 the calicular margin, form generally five cycles of six systems ; in 

 some the fifth cycle is incomplete. The primaries, secondaries, 

 and tertiaries are equal in size, with their inner edges slightly 

 thickened and sinuous before they unite by means of thick 

 nodular trabecuhe to form the loose parietal columella. Occasion- 

 ally two or three of the quaternaries are similarly thickened and 

 united with the columella. All the septa are ornamented with 

 radiating ridges bearing small spines. 



Localities and the relation between the height of the coi'allum 

 and the calicular arid basal measurements, with the variation in 

 the number of root-like processes of the epitheca, are given in the 

 accompanying table. 



Flahellum ruhruin. 



No. of 

 specimens. 



Localitj'. 



Station XXV. Gregorj' Group. 

 Bottom : stones and 



broken shell. 

 Deptli : 4-14 fathoms. 



Station XXV. Gregorj' Group. 

 Station XXIV. Cat Ishuid. 



Bottom : rock, sand, 

 and broken shell. 



Depth; 8-22 fathoms. 



Station XVI. Alligator Rock. 

 Bottom : rock and sand 



or mud. 

 Depth : 8-18 fathoms. 

 Station XVIII. Paye Island. 



Bottom : sand, shell, 



and rock. 

 Depth : 10-21 fathoms. 



Station XVIII. Paye Island. 



Station XVIII. „ 



Station XVIII. „ 



Station XVIII. „ „ 



Station XVIII. „ 



Station XVIII. „ 



Station XV III. „ 



Height of 



Corallum 



in mm. 



Calice 

 in mm. 



27 



Y 19 



I Basal Number 

 I scar of basal 

 I in mm. processes. 



29 X12 



8X4 



r 25 35 XlO llXf 



22 XlO! 8X4 



