r.ErORT ON THE ALCYONARIA. 189 



The main axis is 4 mm. in diameter at its base, narrowing to 2'5 mm. at its termina- 

 tion. The diameter of the hranches at their origin is 3 mm., and they taper gradually 

 to a diameter of 2 mm. at their tips. In the second specimen, which has been torn 

 from its attachment, the third and fourth branches give off also smaller twigs, and in the 

 case of the third branch the first twig given off again ramifies. The whole colony is 

 larger than in the other specimen, the basal diameter of the main axis being 5 mm., and 

 its length is at least 34 cm. The origin of the branches at the main stem is in several 

 instances enlarged. The axis and branches are cylindrical. 



The verrucas are numerous, and closely but irregularly packed on the stem and 

 branches, they are very slightly elevated ; the polyps are completely retractile within 

 them. In the larger specimen the verrucae are more distinctly elevated. The distance 

 from centre to centre of the verrucae is from 0"5 to 1 mm. The foliar expansions of the 

 peculiar club-shaped spicules stand out, forming a margin to the verrucae. 



The polyps are completely retractile, the tentacles being first withdrawn slightly 

 inwards and then the whole pol^'p body is retracted ; the walls of the verrucae are also 

 capable of contraction ; the bodies of the jaolyps are destitute of spicides, but there is a 

 well-developed collar of needle-shaped spicules around the base of the tentacles, and two 

 curved, needle-shaped spicules run from this along the outer basal portion of each 

 tentacle; between which there is generally a third. 



The coenenchyma is comparatively thin and somewhat friable, its outer portion is 

 rough, and consists of the large, club-shaped spicules, and beneath these are simple or 

 branched, spiny spindles and tri- and quadriradiate spiny forms. 



The spicules are as follows : — The foliaceous clubs have a short, thick neck, from 

 which project downwards one, two, or three spiny arms, often these are much branched ; 

 the foliaceous portions are very irregular in outline, thicker where they rise from the 

 neck portion, they soon narrow to an edge, whicdi varies from a semioval to a triangular 

 form. The edges are sometimes smooth, sometimes jagged ; on the constricted portion 

 tubercles occur in the older forms. They measure 0'6-0'3 ; 0"G-0"4 ; 0"4-0'56 ; 

 0"3G-0"4 ; 0'2G-0'22 mm. The sjjiny spindles are sometimes simple, at other times 

 branched. They measure 0-6-0-1 ; 0-3-0-1 ; 0-2-0-06 ; 0-18-0-04 mm. The branching 

 spiny spindles gradually merge into irregular tri- and sexradiate forms, measuring across 

 the arms 0-46-0 -26; 0-3G-0-2 ; 0-3-0-2; 0-2-0-2 mm. In the tentacles or at their 

 base the curved spicules measure from tip to tip 0"2 mm., with a diameter to each arm 

 of 0'04 mm. The straight spicules measure 0'3-0'04 ; 0'2-0'04 mm. 



The general colour of the colony is a deep brownish-red ; the polyps being of a pale 

 yellow. The axis is tough, flexible, of a dark black colour. The species had been 

 selected for figuring (1883) as new, but seems to be merely a variety of Plexauroides 

 pnelonga (Ridley). 



Habitat. — Station 186, Cape York; depth, 8 fathoms; bottom, coral sand. 



