DUNCANIA BARBADENSIS. 45 



Duncania barbadensis x. bp. 

 PI IX. figs. 5, 6, 7. 



Corallum cylindrical, obliquely attached, covered with a thick wrinkled 

 epitheca, which rises above the margin of the calicle, and sends out folds on 

 one side, which fasten to the body on which the coral grows. No costas dis- 

 cernible. Fossa circular, not deep. Septa not projecting above the edge 

 formed by the epitheca, and leaving a concave border between their outer 

 edge and the epitheca; rounded, rather thick, entire, with granulated sur- 

 faces. There are no distinct systems ; the normal number of septa appears 

 to be twenty, though there are sometimes one or two more or less ; alternate 

 ones are slightly smaller, and have one or two, sometimes three, paliform lobes 

 little different from the columella* Between these twenty principal septa 

 which appear to belong to two cycles, there are rudimentary ones of a third, 

 which mostly remain in the condition of flat ridges against the wall. Colu- 

 mella formed by a dense cluster of pillars, varying from ten to twenty in 

 number. The interseptal chambers are not very deep, the whole interior of 

 the coral being filled up solidly for nearly two thirds of the height ; a vertical 

 section shows no trace of separate tabulae or dissepiments in the solid mass. 

 All the specimens have a very oblique plane of attachment, so that, resting 

 on a horizontal surface, the calicle stands at an angle of about 60". The 

 position of the longer diameter of the mouth of the polyp bears no constant 

 relation to the inclination of the base. 



The polyp is deep flesh-colored, and conformed exactly as in Haplophyllia ; 

 the tentacles are about 25 or 30 in number, conical with inflated tips. The 

 sphincter closing over the retracted tentacles is considerably above the mouth, 

 and when contracted forms between the disk and mouth a well-defined pre- 

 buccal cavity, as it is called by Duchassaing. 



Height 20-25 mm., diameter 10-11 mm. Several specimens were ob- 

 tained in 100 fathoms off Barbados. 



* The number of twenty septa is frequently found in the Stauridie and Cyathaxonidie, where there are 

 four systems with unequally developed cycles. 



