30 Transactions of the Society. 



will show the impossibility of linking the specimens now under 

 consideration to any of tliese genera. It will be shown that it is 

 necessary to establish a new genus. 



As a full description of the Juncclla spiralis type has been 

 given by Hickson,* we may briefly consider some of the most 

 characteristic features before proceeding to any taxonoinic con- 

 sideration. The colonies were all unbranched ; one of them was 

 220 mm. in length without the base, which had been broken off. 

 The axis was pale brown in colour, and had rings of lime embedded 

 in the horny matrix. The verruca; were all prominent and 

 arranged irregularly on two-thirds of the circumference of the 

 stem.''leaving\ bare track on one side free from verrucas from end 

 to end of the colony. The bare track and verrucye were covered 

 with a dense armature of spicules, and " it is difficult to believe 

 that the verrucse can ever be retracted." The spicules consisted 

 chiefly of irregularly tuberculated plates and spindles. "The 

 spicules are tightly jammed together to form an impenetrable 

 armour. The surface of the verrucse has a distinctly squamate 

 appearance, the plate-like spicules slightly over-lapping." 



Hicksonella f spiralix g.n. ( = Juncclla spiralis Hickson). 

 Plate XIII. tigs. 1-3. 



Two specimens referable to this species occur in a collection 

 from Cape Colony. Professor Hickson very kindly sent me a 

 small portion of his type specimen for examination, and one of 

 the present colonies agrees with it ia almost every feature. It is 

 40 cm. in length, the diameter is 3 • 5 mm. near the base, and about 

 2 mm. at the tip. The tapering is thus very gradual, in fact at a 

 distance of 7 cm. from the tip there is very little difference in the 

 diameter from that at the base. 



Another specimen is 20 cm. in length, and has a maximum 

 diameter of 2' 5 mm. at the base. In Loth specimens the basal 

 part is wanting. 



The axis is densely calcareous, and very hard in the lower 

 portion, so that, except near the apex, the colony is very rigid. It 

 is composed of concentric laminae of the typical Gorgonellid type. 

 There is a distinct, central, more densely calcareous portion, and 

 the surface is marked by a series of minute longitudinal furrows. 

 The diameter near the present base is 1 • 5 mm., but this diminishes 

 gradually to a hair-like fineness at the tip. 



• The Alcyonaria of the Cape of Good Hope. Part [II., Marine Investiga- 

 tions in South Airica, iii. (1904) pp. 231-33 (4 figs.). 



t I wish to associate with this new and remarkable genus the name of Pro- 

 fessor Sydney J. Hickson, D.So. F.R.S., who has done so much to elucidate the 

 structure and relationship of Alcyonarians, and to whom we are indebted for the 

 original observations on Hich$onella. 



