71 



Acamptogorgia bebrycoides, von Koch, var. robusta, n. Plate III. 



figs. 7 and 8. 



The colony is branched in one plane, most of the branches being given off 

 at one side. The tips of the twigs are somewhat club-shaped, and occupied by 

 three polyps. The general coenenchyma is rough in appearance. There is no 

 trace of a basal attachment. 



The axis is horny, yellowish in colour, and marked by a number of longi- 

 tudinal strife. The centre is composed of chambers separated from one another by 

 transverse walls, and containing a w^hitish substance which gives little or no trace 

 of effervescence when treated with acid. The cavity is not quite central, but lies 

 sometimes nearer one side, sometimes nearer the other. 



The polyps occur all over the surface of the main stem or branch. The 

 verrucpe are almost cylindrical, but somewhat squat, 1'5 mm. in height, with 

 a basal diameter of 1"3-1'7 mm. A number of spines project round the 

 apex. 



The retracted anthocodise bear an almost hidden low conical eight-rayed 

 operculum, which is formed by the infolded tentacles. The sjaicules on the 

 anthocodifB are arranged in a crown and points ; the crown consists of 2-3 trans- 

 verse rows ; the points have their sjaicules en chevron, with a number of short, 

 curved spicules at the base of each triangle. 



The coenenchyma is thick, and has an arenaceous ajDpearance. 



The spicules of the anthocodise are spindles, straight or curved, and covered 

 by warty projections. Several are thickened at one end, and present a club- 

 shaped appearance. The following measurements were taken of length and 

 breadth in millimetres : 



0-6x0-l; 0-45x0-04; 0-2x0-03; 0-15x0-02. 



The spicules of the general coenenchyma and of the verrucce are ( 1 ) spindles, 

 straight or curved, with warty projections, or with large, thorn-like projections 

 covered by warts ; (2) incipient quadriradiate forms ; and (3) irregular forms, 

 with two or three rays at one end. Their dimensions, taken as above, are : 



1. Spindles, 0-6 X 0-046; 0-5x0-04; 0-45x0-04. 



2. Quadriradiate forms, 0-4 X 0-25; 0-3 x 0-2. 



3. Irregular forms, 0-4 X 0-2; 0-3 x 0-2. 



The last kind of spicule is extremely irregular ; some seem to be almost flat, 

 with large processes extending from the edges ; others seem to be plates, with 

 spines projecting from them. 



Locality : Station 333 ; 6° 31' N., 79' 38' 45" E. ; 401 fathoms. 



