ALCVOXARIA — J. A. THOMSON AND DORIS L. MACKINNON. 147 



Order II. ALCYONACEA, F^rr/7/ (pro parte). 



Family ALCYONIDAE. 



Genus ALOYONIUM, Linni. 



ALCYONIUM (ERYTHROPODIUM) MEMBRANACEUM, 



Kukenthal. 



Alcyon'min memhranaceum, Kiikentlial, Alcyonacea — Wiss. Ergeb. 

 deutscli. Tiefsee Exped., xiii., 1, 1906, pp. 52-53, pi. 1., tig. 3, 

 pi. ix , figs. 42-44. 



Stations 42, 44, 34, 43. 47. 48. 



Numerous Gorgonid axes, e.g. of Clenocella, are almost covered 

 by Si/mpodium-]i]ie growtlis, whicii investigation shows to be 

 creeping Alcyonids, agreeing on the whole, with Kiikenthal's 

 description of Alcyoniam ( Frylliroporlium) memhranacettm. Tlie 

 ccenenchyma-spicules are verj' variable in form. There are 

 approximately spherical bodies (diameter •08--12 mm.), short 

 thick cylinders with about two bands of thorny warts, foinis like 

 cervical vertebrae, and others of more irregular shape. The 

 polyp spicules are spindles. Below the eight points of converging 

 spicules in the anthocodia there is a deep collaret of about eight 

 rows of horizontally disposed slender spindles. The colour of 

 the colonies is light brown. 



This species presents considerable difficulties to the classifier. 

 In some specimens the Gorgonid axis is so completely and so 

 evenly overgrown with tiie Alcyonid, that it is hard to believe 

 that one is not dealing with tlie natural ccenencliynia. There is, 

 however, a slight tendency to the formation of "independent 

 stocks," and at the tips of the branches the encrustation often 

 forms a well-marked projection beyond the axis. On the more 

 weathered specimens it is instructive to note how the encrusting 

 Alcyouid is brought up sharply against large groups of Ciri ipedes. 

 Sponges, etc., which have also found the Gorgonid axis « suitable 

 place of attachment. 



In the majority of our specimens the internal structure couhl 

 not be made out with certainty, owing to their being in the dried 

 condition, and extremely f liable. In the sipirit-s|iecimens, how- 

 ever, the ccenenchyma shows the Alcyonid arrangement of side- 

 canals between the gastral cavities of the polyps, an arrangement 

 that, in Kukenthal's opinion, removes these SymjmUum-W^e 



