176 THE VOYAGE OF H.M.S. CHALLENGER. 



A single specimen, broken, but with many of the calicles fresh looking, as if the 

 coral had recently been living, was dredged. 



Station 196. Off the Moluccas. Lat. 0° 48' S., long. 126° 58' E. 825 fathoms. 



Neohelia, n. gen. 



Corallum, with a very abundant and diffuse ccenenchym encrusting the stems of 

 Gorgonoids, with very short branches only. Calicles with the septa arranged in five 

 systems, which are often fused together by the ccenenchym ; gemmation irregularly 

 dichotomous. 



Five systems and four cycles of septa ; a deep fossa ; no columella. 



Neohelia porcellana, n. sp. (PI. X. figs. 7, 7 a). 



The corallum rises from a broad base in a thick irregular column, encrusting dead 

 Gorgonoid stems, and the stones to which these are attached. There is an abundant 

 diffuse, bluish-white, semitransparent coenenchym which solders together the branches, 

 and covers the invested objects so as completely to hide them. The central column is 

 composed partly of fused branchlets of the coral itself, partly of invested gorgonoid 

 structures. Many of the branchlets of the coral, which appear, as if entirely composed 

 of its own structure, are found when broken, to be traversed internally by a flexible 

 Gorgonoid branch almost as large in diameter as themselves, as seen in a broken 

 branch in the specimen represented in figure 7, on the right hand side in the sketch. 

 Besides these encrusting branchlets, the corallum bears also all over some very short 

 branches, which are solid and composed of its own structures entirely. The surface of 

 the ccenenchym is marked all over by very slightly elevated rounded ridges which 

 traverse it irregularly, but with a general longitudinal direction, and are continuous at 

 the margins of the calicles with the costge. The gemmation is irregularly dichotomous. 

 The calicles are small, and circular in outline. There are uniformly in all the 

 calicles five systems of septa, and three cycles — twenty septa in all. The septa of the 

 three cycles are distinctly unecpial. The septa are very slightly exsert, and are con- 

 tinued just over the margin of the calicle as very short costse ; they are straight, smooth, 

 and thin-edged, near the mouth of the calicle ; but deep down, within the fossa, their 

 fine margins become thickened and sinuous, and covered with granules, and the 

 primaries and secondaries meet one another, but without the formation of a columella. 

 On the young branches the calicles are short and cylindrical ; on the main stem they 

 become buried up to their margins, or obliterated by the ccenenchyma. 



All the three specimens obtained encrust Gorgonoid stems in a closely-similar 

 manner ; two of them encrust also stones to which the Gorgonoid stem is attached. I 

 have counted the septa in a very large number of calicles, but have found them alike 

 in all, namely, twenty, so that in this matter the coral resembles certain species of 



