REPORT ON THE ALCYONARIA. 81 



refers to fig. 14 as Juncella vetusta, doubtless he regarded the axis as belonging to a 

 Gorgonellid, and hence Gray's inclusion of the same under Primnoella is apparently not 

 justified. 



In 1878 Studer placed three new species in the genus, all collected by the " Gazelle " 

 from deep water in the southern hemisphere {op. cit.). At the same time the generic 

 diagnosis Wfis somewhat modified by him. He characterises the genus thus : — " Coral 

 simple, unbranched. Axis horny, calcareous. Bark thin. The polyp cells around the 

 stem in regular whorls of more than three cells. Cells covered with small overlapping 

 scales, which are mostly unsymmetrical and toothed on the edges." 



Three more species were collected by the Challenger, so that thereby the number 

 of known species amounts to seven. 



The colony consists of a simple, at times much elongated stem, which ascends from a 

 root-like portion, which affixes itself to foreign bodies. On the stem are placed the calyces 

 in whorls of from four to twenty, the distances between two whorls (the intemodes) 

 may be longer or shorter than the calyces. The root is always calcified, it either forms a 

 disc-like calcareous lamella, or it consists {Primnoella distans) of branched, stolon-like 

 processes, which are either embedded in the mud or hold on to foreign bodies. The axis 

 is on an average thin, often quite thread-like, it is in individual species completely 

 horny, flexible and elastic, in others calcareous and brittle towards the base, but further 

 up the stem it is flexible. 



The coenenchyma is very thin on the intemodes and contains only a single layer of 

 flat, scale-like, calcareous spicules. The calyces are distinctly bilateral, their transverse 

 section oval, the shorter axis is placed perpendicularly to the long axis of the stem. One 

 can accordingly distinguish a dorsal portion, turned away from the stem, a ventral portion, 

 turned towards the stem, and two lateral portions. The calyx scales form perpendicular 

 rows, the elements of which, however, are not parallel to one another, but are inclined 

 towards one another, mostly about half the height of a scale, and the upper edges 

 of which project above the base of the succeeding one ; in like manner the scales of one 

 row usually overlap those of the next with their lateral edges. The scales of the ventral 

 side are smaller and flatter than those of the dorsal side, which are often sculptured or 

 provided with spines. 



Around the mouth of the calyx the scales form an operculum-like crown of eight 

 scales, which are mostly elongated and three-cornered and appear more or less strongly 

 developed. These opercular scales always arise inside the last circle of the calyx scales 

 and exhibit a distinctly bilateral arrangement. Two dorsal scales and two ventral ones 

 are always placed opposite to one another, and there are always two lateral ones. 

 These opercular pieces are always arranged so that the dorsal scales may overlap the 

 next ventral ones with their edges, and so that the two ventral opercular scales come to be 

 deepest, and close the calyx like a lower lip. The spicules of the operculum are either 



(ZOOL. CHALL. EXP. — PART LXIV. — 1887.) SsS 1 1 



