30 



The present writer would define the genus Muricella as follows : Calyces in the form 

 of truncated cones or rounded verrucae. The spicules are all spindles, those of the coenenchyma 

 very large, arranged longitudinally. The upper portion of the calyces with smaller, vertical 

 spindles often forming eight marginal points by the convergence of their upper ends, thus 

 forming a sort of approximation to an en clievron arrangement. The tentacle bases have 

 the spindles arranged en chevron. 



The genus thus differs from Muriceides in having very large spindles, from Paramuricea 

 in the form of the calyces, and from Anthomuricea in having the spindles of calyx walls not 

 en chevron. 



The type species of this genus is Muricella flexuosa (Koll.). 



The known species belonging to this genus are M. ceylonensis Thomson and Henderson, 

 M. complanata W. and S., M. crassa W. and S., M. nitida Verrill, M. perramosa Ridley, 

 M. ramosa T. and H., M. rubra Thomson, M. tcnera Ridley, M. tuberculata (Esper) and 

 M. unibraticoides Studer. To these must be added the three new species described beyond. 



i. Muricella gracilis Wright and Studer. 



Muricella gracilis Wright and Studer. Challenger Reports, the Alcyonaria, 1889, p. 129. 

 Stat. 274. 5 28'. 2 S., I34°53'.9E. near Aru Islands. 57 meters. Sand and stones. 



Colony roughly pinnate, straggling in habit, 5.2 cm. in height, and with a spread of 

 about 2 cm. The main stem gives off six short simple branches from one side, and one bifurcated 

 one from the other. The distance between branches is about 5 mm. The calyces are arranged 

 in a long spiral, and the branches end in a polyp. The distance between calyces is about 

 2 mm. on the average. 



The individual calyces are tubular in form, and a typical one is a little over 1 mm. in 

 height, and about as broad as long. lts walls are filled with vertical spindles, there being 

 usually a fairly regular basal set between the distal ends of which are fitted smaller spindles 

 that reach to and surround the margin. In some cases these latter tend to arrange themselves 

 en chevron. The polyps are entirely retractile, and the operculum is composed of a number 

 of small spindles which seem to be arranged in 110 definite manner, although there is a tendency 

 toward an en chevron disposition. The coenenchyma is filled with large spindles characteristic 

 of this genus. 



Spicules. These are all spindles of various sizes, some of which attain a length of 

 2 mm. They are rather more slender than is usual in this genus, and their edges are closely 

 approximated in the coenenchyma. They are covered with small, closely set tubercles. 



Color. The colony is a bright coral red throughout, and the spicules are of the same tint. 



General Distribution. Admiralty Islands. 16 — 20 fathoms. 



The spindles of this species resemble those of the genus Acis in the way in which 

 their edges are fitted together. 



