4 Thomson, Cavernularia, Liitkenii, Koll 



0.19 mm. lang, 0.013 — 0.044 mm. breit, die des Kolbens 

 Walzen — , spindel — oder kolbenformig ohne Theilungen an 

 den Enden, 0.11 — 0.31 mm. lang, 0.01 — 0.06 mm. breit." 



The following different species of the genus Cavernularia 

 have been described: — C. obesa M.E. & H. 1857; C. elegans 

 Herklots 1858; C. Chuni Kiikenthal and Broch, 191 1; 

 C. Herdmanni Simpson, 1905; C. madeirensis Studer, 1878; 

 C. Habereri Moroff, 1902; C. marquesarum Balss, 1910; 

 C. glans Koll., 1872; C. malabarica Fowler, 1894; C. orientalis 

 Th. & S., 1909; C. andamanensis Th. & S., 1909; C. Liitkenii 

 Koll., 1872; C. pusilla Herklots, 1858; C. clavata K. & B., 191 1. 



This species has considerable superficial resemblance with 

 Cavernularia glans, Koll. as figured by Kiikenthal in the 

 "Valdivia" results. It also comes near Cavernularia obesa, 

 Milne-Edwards & Haime and C. Habereri, Moroff. From the 

 former it may be distinguished by the presence of an axis in the 

 interior of the stalk, from the latter by the occurrence of 

 spicules in the middle region of the cortex of the rachis. 



The special interest in recording this species is that it 

 occurs off the Coast of Natal and that the other specimens 

 which were recorded by Kolliker and by Thomson and Simpson 

 were taken farther north in the Indian Ocean. It is well known 

 that the coast of Natal is washed by a warm current (Mozam- 

 bique) from the Indian Ocean. This species has, however, 

 not been found to occur on the West Coast of South Africa 

 which is washed by the cold polar or Benguela current, and its 

 habitat is within the 20 degrees isotherm of August as shown in 

 physical maps. 



The Genus Cavernularia belongs to the family Veretillidse, 

 the other genera belonging to this family being Lituaria Valen- 

 ciennes, Veretillum Cuvier and Actinoptilum Kiikenthal. 



The general characters of the family Veretillidse are the 

 following : — Zooids evenly distributed on all sides of the rachis, 

 the latter without external signs of bilateral symmetry. The 

 colonies stout, club shaped or cylindrical, the autozooids and 

 siphonozooids without any definite arrangement in horizontal 

 or longitudinal rows. The spicules, double clubs or "capstans," 

 spheres or ovals, flat plates or rods, minute otolith-like corpus- 

 cles or altogether absent. Axis extending the entire length, 

 or short and incomplete or absent. 



It is interesting that at first sight I regarded this form as 

 one of the Alcyonacea, as Hickson in his recent monograph 

 on the Siboga Pennatulids has brought forward the view that 



