106 



The stalk measures 2 5 cm. in length, about one-quarter of the total 

 height of the colony. It is thick and somewhat flabby, granular in appearance, 

 and gives off from its base a large number of long, slender stolons to which are 

 attached particles of sand and fragments of shells. 



The polyparium is large, compact, solid, of oval outline and somewhat 

 flattened ; it is thicker towards the apex than at the base. It is formed of a 

 large number of very thick short cylindrical branches which by numerous re- 

 peated divisions give rise to the polyp-bearing twigs. In the lower part of the 

 polyparium the branches are small, much larger towards the middle, and again 

 slightly smaller as the upper part is reached. The branches may be said to be 

 given off in irregular whorls, but the branches of one whorl are by no means of 

 uniform size. The main stem ends in a very blunt conical projection which 

 shows traces of dividing into three lobes, the beginnings of three new branches, 

 on each of which there are numerous polyjjs. 



The polyps all come to the surface of the polyparium and are arranged in 

 groups of six to twenty individuals each. A number of .groups lie close together 

 and form larger groups which are flat to slightly hollow in surface. These 

 groups vary in shape from O to D or A and are themselves grouped with 

 other large groups, thus forming huge flat to concave, circular to angular 

 bundles of polyps in which there are several hundred individuals. The polyps 

 are placed on very short stalks about 5 mm. in length. They are small 

 rounded bodies measuring about 0*48 mm. in length by O'OO mm. in breadth, 

 and standing at an obtuse angle to the stalk. The polyp-spicules are 

 arranged in eight double rows in each of which there are six to seven pairs 

 of converging spicules which have few spiny protuberances and measure on 

 an average 0"21 mm. in length. There are no specially large forms and 

 none project. Two rows of spicules occur on the aboral surface of the ten- 

 tacles. 



The Stiitzbiindel is not very well developed, being seen at its best on the 

 outer polyps of each bundle, where a spicule may reach a length of 1"8 mm. 

 and may project for a short distance. 



Cortical spicules : (a) Those of the stem are slender s|)indles, straight or 

 curved, covered with regularly arranged roughened warts. They vary from 0"33 

 to o'O mm. in length, and from UiJG to 0'18 mm. in breadth. They are irregularly 

 arranged, producing a stringy appearance. 



(/>) Those of the stalk include numerous spindles, clubs, tri- and tetra- 

 radiate forms, and also irregular spindles or stars. They are covered by irregu- 

 larly arranged, pointed or blunt, large rough thorns. The spindles measure 

 up to O'G mm. in length. 



Canal-wall spicules : (a) The stem contains large spindles of a peculiar 

 stringy appearance, with very few blunt, thorn-like projections, and numerous 



