the character of the costae, in having wide interseptal locuii, 

 in the character and ornamentation of the septa, and in the 

 nature of the columella. 



The specimens, however, are larger than the type, i.e., have 

 a wider calicle ; the six from No. 1. above, varying from 1 2 x 

 io*5 mm. to 9 X 8 mm., and averaging 10 x 9-2 mm., while the 

 specimen from No. II. is obviously young. They are very 

 slightly curved, and their p-rowth appears to have been vigorous. 

 All are relatively thin and dehcate compared to the types. In 

 the six apparently adult specimens, the full number of septa 

 of four cycles are present, and in one specimen there are two 

 septa of a fifth cycle. The septa of cycles I. and II. are sub- 

 equal, varying up to 2 mm. in exsertness, rounded above, but 

 ending almost perpendicularly against the axial fossa ; deep 

 down in the calicle — scarcely visible from above — they meet 

 the columella. The tertiary septa are a little larger than the 

 quaternary, but much more delicate, and only about half as 

 broad and exsert as the first twelve. A little below the top of 

 the columella they extend in almost horizontally to join it, com- 

 monly rising a httle, this part generally ending above in a 

 v/avy edge. The columella consists of a series of slightly 

 twisted, thin, anastomosing, plate-like lamellae, the whole in the 

 largest specimens forming about a quarter of the diameter of 

 the calicle, but in the smaller decreasing down to a sixth or 

 seventh. 



The series of arched thickenings on the septal sides, parallel 

 to their upper inner edges, described by Duncan, are most 

 noticeable and peculiar. I do not find any record of their oc- 

 currence in any other member of the Turbinolidae, though I 

 have myself found them in a fragment of a coral apparently be- 

 longing to the genus Diincania from the Cape. Superimposed 

 on them transversely, and continued into the valleys between, 

 are the minute ridges, which, corresponding to the so-called 

 " lines of growth," seem to be a constant feature in the family. 



None of the specimens show any definite external growth 

 lines, though one had evidently been partially killed at one edge 

 of its calicle, but grew out again, the polyp subsequently en- 

 closmsf the whole corallum as before. None likewise show any 

 definite marks of attachment, but it is quite evident that all 

 reallv were derived from fixed stocks. One specimen ends 

 basally in three points. One of these appears properly to be 

 the point, the other two having arisen in the regeneration which 

 succeeded some injury. 



The specimen from No. II. is a young form, with only 14 of 

 the quaternary septa developed, though the rest are complete. 

 The characteristic appearance of the axial fossa, so largely 

 broug-ht about by the continuations of the tertiary septa into 

 the axial fossa, is not as yet developed, though clearly indi- 

 cated. 



