ALCYONARIA — J. A. THOMSON AND DORIS L. MACKINNON. 667 



Nearly all the specimens are complete. From a slightly 

 encrusting base rises a stout stalk-portion, with a diameter, in 

 the largest specimen, of 4-5 cm. This stalk is of very firm con- 

 sistency, and has a rather harsh, wrinkled surface. The poly- 

 parium of the smallest specimen is unbranched and club-shaped. 

 In all the others at a height of 2-3 cm. the stalk-portion divides 

 up into a number of stout, diverging, finger-like lobes, 1-2 cm. in 

 diameter. These subdivide into secondary lobes, usually from 

 0-5-1 -75 cm. in height, with diameters ranging from 1 cm. to 1*75 

 cm. Upwards from a point about '5-2 cm. from the base, the 

 entire colony is covered with polyps which, in most of the speci- 

 mens, are retracted into low, rounded, eight-lobed calyces. The 

 average distance between two polyps is 1-5 mm. The polyps, 

 when fully expanded, have a length of 3"5 mm. They are marked 

 with eight longitudinal grooves, and just below the level of the- 

 tentacles they are armoured with eiglit isosceles triangles, each, 

 composed of 8-10 converging pairs of slender spicules. Near the 

 base of each triangle these meet at an angle of about 45° ; higher 

 up, they ai^e almost parallel ; but very occasionally one or two are 

 directed horizontally below the triangular points. The tentacles 

 are entirely without spicules : they are long and feathery, with 

 about ten long pinnules on each side of the middle line in a 

 single row. 



The whole surface of ccenenchyma appears as though dusted over 

 with a thick sprinkling of small, white, glistening spicules, which 

 bear a resemblance to grains of sugar. These are stout double-clubs 

 and capstan-like bodies with a distinct "neck," and, on an aver- 

 age, two whorls of projecting, tuberculate warts. The following 

 measurements were taken of length and breadth in millimetres : — 

 •187 X -119; -17 X -119; -119 x -102; -085 x -085. Smaller 

 forms ('102 x 068 mm. ; '085 x '051 mm.) approach Kolliker's 

 " Sechser " and are probably young stages of the first. The 

 entire cortex is crowded with spicules of the same form as those 

 on the surface, and similar spicules occur, but nmch more 

 sparingly in the canal walls. 



The spicules of the polyps are spindles and clubs of slender 

 form, with a few projecting warts. Their dimensions in mm. 

 are -306 x -034; -27 x -068 ; 204 x 017 ; -17 x -017. 



The colour of the colonies is greyish-brown to dark-brown ; the 

 polyps are a darker shade of the same colour. 



In many respects this species comes very near to Hickson's 

 Alcyonium purpureum^. 



^Hickson — The Alcyonaria of the Cape of Good Hope, part ii. — Marino 

 Investigations in South Africa, iii., J90t, pp. 215-217, pi. vii., fig- 1, pl.ix., 

 fig. 18. 



