CA R YOPH YLLJA CEA . 
TURBIN on A DjB. 
THE SMOOTH-RIBBED WEDGE-CORAL. 
Sphenotrochus Macandrewanus. 
Plate X. Fig. 4. 
Specific Character. Corallum uniformly diminishing downward; ribs 
smooth, not salient ; edge of calice plane. 
Tarbinolia milletiana. Thompson, Annals N. H. Ser. 1. xviii. 394. 
Johnston, Br. Zooph. Ed. 2, i. 196; pi. 
XXXV. figs. 1 — 3. E. P. Wright, N. H. 
Rev. vi. 122. Gosse, Man. Mar. Zool. i. 
32 ; fig. 49. 
Sphenotrochus Andrewianus. M. Edwards and Haime, Ann. d. Sci. Nat. 
Ser. 3. ix. 243 ; pi. vii. fig. 4. 
ilacandreivanus. M. Edwards, Hist, des Corall. ii. 70. 
GENERAL DESCRIPTION. 
Corallum. An inverted cone, compressed, lengthened, straight, with 
the inferior extremity forming a wedge-like blunt point. 
Ribs. Perfectly straight, smooth, nearly equal throughout, or slightly 
enlarged above, separated by intercostal spaces about twice as wide as 
themselves, moderately prominent, continued round the edge of the scar 
where the corallum was originally attached. 
Calice. The edges on the same horizontal plane ; outline elliptical, in 
the ratio of 100 : 120. 
Plates. Twenty-four ; in three complete and well-develojied cycle.s, 
close-set, straight, thick at the margin, and gradually thinning towards the 
centre of the calice ; salient, arched at their upper edge, with a surface very 
slightly granulose. The primaries and secondaries are subequal and similari 
and hence the appearance of twelve systems ; each of these is united w’ith 
the columella by two diverging laminae, as if the j'late were split at its inner 
edge, and the two halves separated. 
Columella. A single, thin, vertical lamina. 
Size. 
Height half an inch ; diameter of calice one-fourth of an inch by one-fifth. 
