10 STENOCYATHUS. 



Stenocyathus vermiformis Podrt. 

 Coenocyathus vermiformis, Pourt. Bull. Mus. Comp. Zoo!., No. 7. 



Plate I, figs. 1 and 2; Plate III, figs. 11, 12, and 13. 



Corallum very elongated, cylindrical. Cost^ indicated only by 

 lines of very flat tubercles. Calicle circular, shallow. Septa rather 

 thick, flexiiose, not exsert, in six systems of tln-ee cycles. Pali 

 thick, curled, in front of the secondary septa. Frequently one of 

 the systems remains incomplete, and there are then but five pali. 

 Columella of a single twisted process. The older parts of the corallum 

 are nearly filled np by the thickening of the septa, but the process is 

 never carried out to a total obliteration of the interseptal chambers, 

 which can be traced in the shape of slender canals to the very base. 



The costal tubercles are hollow, and communicate through narrow 

 canals with the interseptal chambers. These little cavities are no 

 doubt homologous to the hollow roots of Rhizotrochus, Thecocyathus, 

 and other genera of the family, but here their use is not apparent. 

 (See Plate III., fig. 13, representing part of a horizontal section passing 

 through these cavities.) 



A singularity is the frequent occurrence of specimens having a 

 living and growing polyp at either end (Plate III., fig. 11). These 

 specimens are generally somewhat curved, having apparently been 

 lying in the mud with both ends turned up and projecting. A 

 longitudinal section shows no interruption in the continuity of the 

 interseptal chambers from one end to the other, so that the diges- 

 tive cavity is probably common to both polyps. 



Height, 2.5 to 4 cm. ; diameter, 2 to 3 mm. 



<^)ff Boca Grande, in 125 fathoms. 

 Off Key West, in 135 fathoms. 

 Off Key West, in 138 fothoms. 

 Off Sombrero, in 152 fathoms. 

 Off Sand Key, in 154 fathoms. 

 Off Tennessee Reef, in 1 74 fathoms. 

 Off Bahia Honda, in 1 76 fathoms. 

 Off Sombrero, in 183 fathoms. 



