14 



Acanella Gray (emended by Veriill). 



Acanella Gray. Catalogue Lithophytes in British Museum, 1870, p. 16. 



Acanella Verrill. Bulletin Museum of Comparative Zoology, Vol. XI, N" i, 1883, p. 13. 



Acanella Studer. Versuch eines Systemes der Alcyonaria, 1887, p. 44. 



Acanella Wright and Studer. Challenger Reports, the Alcyonaria, 18S9, p. 29. 



Acanella Nutting. Hawaiian Alcyonaria, 1908, p. 572. 



Verrill's definition of the genus is as follows : 



"Coral either simple or variously branched. Axis with long calcareous joints and very 

 short horny ones. The branches, where they exist, arise from the horny joints, either singly, 

 or two or more together, often forming a whorl. Coenenchyma very thin, containing, more or 

 less abundantly, elongated fusiform spicula, usually of large size. Calicles large, elongated, 

 composed of large fusiform spicula, often obliquely arranged ; the margin is armed by eight long, 

 spine-like, projecting acute spicula. Tentacles stiflened by abundant spicula. Base, in most cases, 

 divided into large, flat, palmate lobes, which descend into the mud and serve as supporting 

 roots or anchors". 



Studer (1887) gives a condensed definition, retaining the essential points as given 

 by Verrill. 



Wright and Studer (1889) retain the definition of A'errill, somewhat condensed, with 

 the additional point that the basal internodes are much shorter than the distal. For the purposes 

 of this work the following definition is offered for the genus Acanella : 



Ccratoisidina, simple or branched, with branches arising from the horny nodes, often in 

 whorls. Calyces prominent, with a crown of marginal points. Tentacles with minute spicules. 

 Coenenchyma thin, with fusiform spicules. All spicules have thorny points, but are without 

 true verrucce. 



The type species of this genus is Acanella arbuscttla (Johnston). Other known species 

 are Aca?iella eburnea (Pourtales), A. chiliensis Thomson and Henderson, A. gregorii Gray, 

 A. nonnajii Verrill, A. rigida Wright and Studer, A. rodiisla Thomson and Henderson, A. 

 simplex Verrill, A. spicnlosa \'errill and the additional species about to be described. 



I. Acanella sibogce new species. (Plate III, figs. 2, 2a \ Plate \', fig. 4). 



Stat. 85. o°36'.5S., 119° 29^5 E. 724 meters. Fine grey mud. 



Stat. 170. 3°37'-7S., i3i°26'.4E. 924 meters. Fine grey mud. 



Stat. 178. 2° 40' S., I28°37'.5E. 835 meters. Blue mud. 



Stat. 211. 5°40'.3S., I20°45'.5 E. I'S^ meters. Coarse grey mud. 



Stat. 241. 4°24'.3S., I29°49'.3E. 1570 meters. Dark sand with small stones. 



Type specimen fragmentary, 7.3 cm. long, the proximal part missing. The largest fragment 

 consists of a central straight shaft from which spring four pairs or opposite branches. In two 

 cases there is a third branch origin between the bases of the opposite pairs, showing a tendency 

 toward the formation of verticels so common in this genus, the verticels being 1.4 cm. apart 

 and springing from the horny internodes, which are so narrow that they constitute mere bands. 



