REPORT ON THE ALCYONARIA. 7 



outer layer of sc<alcs or spiudle-sliaped calcareous bodies, which overlap one another on 

 opposite sides and exhibit a very fine sculpture, which, however, can only be made out 

 with a somewhat high magnifying power ; and an inner layer of small plates, at times 

 branched, which are united with one another by toothed edges and often exhibit a double 

 or four-fold structure. 



The polyps are not retractile, the tentacles which arc armed with spicules protect 

 the mouth-opening by folding in over it. 



The axis is, for the most part, horny, iridescent on the surface. The base is always 

 calcified. 



Verrill ^ included in the genus Dasygorgia a number of species of his Chrysogorgidai, 

 which in several characters seem separate from the genus Chrysogorgia, with which 

 they have the mode of branching in common. 



Verrill's diagnosis runs : — " Coral much Ijrauched, often spirally, the branches 

 repeatedly forking. Calicles obliquely placed on the branches, swollen at base, covered 

 with flat, oblong spicula, which are arranged longitudinally or obliquely. Spicula of 

 the coeuenchyma oblong or scale-like, nearly smooth." Verrill refers to this genus five 

 species, all from more or less deep water ofl" the coast of New England and the West 

 Indian Seas. 



The ramified Dasj-goi'gidse of the Challenger collection may all be referred to this 

 genus, but the diagnosis requires to be considerably emended. 



The colony always consists of a main stem, which rises from a calcareous basis, and 

 of branches, which come ofi" from it almost at right angles. 



The stem is upright ; its axis consists of very close, concentric, horny fibres, with 

 calcareous deposits. Occasionally only it is flexible and elastic near the point. Its 

 colour is golden to a dark brown, the surface is iridescent with metallic reflections in 

 inilividual places. The stem axis is never straight, but always exhibits, at the places 

 where the branches come off", an angular bending, the apex of the angle indicating the 

 origin of the l)ranch. If tlie branches arise from the stem in alternating series, the axis 

 shows a zigzag bending along its course. Frequently a sjiiral twisting of the stem is 

 associated with this. In the simplest case the branches arise from the stem in alternating 

 series from the two opposite sides ; they frequently arise from tliroe sides in .short, 

 ascending spirals, and in individual cases they arise from five sides in spirals that follow 

 closely upon one another. The ramification of the branches is again highly characteristic, 

 and may best be compared with the form of the uniparous helicoid c}Tne common in plants. 



Every branch gives off twigs from one side only, and every twig may, in the sjime 



way, bear lateral twigs, which may further anastomose. At the point where a twig or a 



lateral twig is given ofi", the main twig is bent at an angle in the opi)osite direction. 



Hence the appearance of bifurcation frequently arises, the twig that comes off forming a 



' Bull. Mus. Comp. Zo'61, vol. xi. No. 1, Report on the Anthozoa dredged by the " Blake," p. 21. 



