12 LEPTOCYATHUS. 



the secondaries about the middle of the radius. Tliere are indis- 

 tinct traces of pali. 



I have satisfied myself that the former determination of this coral 

 was wrong- ; it is probaJjlv a free Paraeyathus, not ver}" unlike P. 

 can/oj)Ji//lhis M.-Edw. and H. 



Height 3 nun., diameter of calicle 2 mm. 



Off the Samboes, in 237 fiUhoms. 



LEPTOCYATHUS M.-Er>w. & H. 



Leptocyathus Stimpsonii Pourt. 



Plate III, figs. 1, 2, and 3. 



Corallum free, more or less hemispherical, without mark of ad- 

 herence. Costie equal, continuous with the septa, without definite 

 boundary, finely serrate and spinous, dee])ly separated by very 

 narrow fnrrows, so that the wall proper is invisible. The ])rimarv 

 costjB reach nearly to the centre, those of the Iburth order eml)race 

 and unite with those of the tliird, and the resnltant costiu of two half- 

 systems unite below the secondaries. This arrangement is seldom 

 regular except in the young, as the base of most of the old ones has 

 the ajjpearance of having been broken and mended, thns introducing 

 much confusion in the arrangement. Calicle circular ; fossa small 

 and not deep. Septa sube(iiial. finely denticulate, the teeth ])ecoraing 

 larger towards the iuterioi'. crowded, in six systems and four cycles; 

 the arrangement of the diifcreiit orders as in the cost:\?. Pali in I'ront 

 of the secondary septa very distinct, those of the other orders scarcely 

 distinguishable from the columellar processes, of wliich there are from 

 six to twelve, crowded and irregularly j^rismatic. 



The young are almost spherical, the calicle being quite small ; they 

 resemble a Melo(Mictus deprived of its S2)ines. 



The polyp is of a delicate jjink or sometimes greenish color, with 

 simple conical tentacles. 



Diameter H to 7 nun. ; height about 3 mm. 



Abunchint in (10 fathoms ofi" Conch Reef; one specimen in 100 fath- 

 oms off Teiuie.ssee Reef 



This coral is referred to the genns Leptocyathus with some doubt, as 

 its denticulate sc'pta would really remove it altogether from the fauiily 

 of Turbinolidaj, 



