102 THE VOYAGE OF H.M.S. CHALLENGER. 



a similar manner as the chief stem, and these may again have simple lateral projections 

 with unilateral poly2:)S. Branches and twigs form between them angles of 45° to 60°. 

 The height of the whole colony is about 120 mm., that of the principal stem is the same, 

 of the larger branches 90 mm. The simple terminal twigs have a length of 40 mm. 

 The diameter of the main axis at its base is 2 "5 mm., of the chief branches 1 to 1*5 mm. 

 The polyps are scattered on the stem and branches at intervals of 1 to 1 "5 mm. They 

 come off principally from opposite sides and leave the middle of the stem free ; on the 

 smaller Ijranehes they arise alternately from both sides. Towards the end of the branches 

 they are placed closer, so that these appear thicker. At the ends of the branches there 

 are usually three or four polyps from the one spot, diverging towards different sides. 

 The form of the calyx, as compared with those of the previous species, is more cylindrical ; 

 the length with the operculum is 1'3 mm., the diameter 1 mm. 



The arrangement of the spicules is the same as in the previous species; but their form 

 differs materially. The spicules of the cceneuchyma are spindles, curved, often with 

 unilateral prominences or spines, there are sometimes also branched or forked as well as 

 simply acerate forms of spicules. These measure 0'33 and 0'3 mm. The eight rows 

 of " Stachelplatten " consist of spicules measuring as follows: — 0'3-0'25 ; 0"23-0*16 ; 

 '26-0' 16 mm. The coUeret is formed of strongly curved spiny spicules, measuring 

 0'38-0'33 mm. At the base of each tentacle, in the middle, is a straight spiny spicule, 

 on which two curved spindles from either side converge, these have a length of 0"35 ; 

 0'3 and 0"25 mm. The axis is brown, fibrous and flexible. In the branches it is soft', 

 so that these have quite pendulous terminations. The colour of the stem in spirit 

 specimens is yellow ; when dried it is white. 



Habitat. — Station 310, Sarmiento Channel, Patagonia; depth, 400 fathoms; bottom, 

 blue mud. 



3. Paramuricea ramosa, n. sp. (PL XXVI. fig. 1). 



In this sjjecies the colony Ls upright, expanded in one plane ; fan-shaped. The 

 principal stem gives off, quite close to the base, a large diverging Ijranch at an angle of 

 48°, which has the same thickness as the principal stem. Each of the two then gives off, 

 at intervals of 15 to 20 mm., large branched twigs and smaller simple lateral branches, 

 which arise at angles of about 45°, giving the impression of a dichotomy. Towards the 

 apex of the colony single branches anastomose with one another, in one instance the 

 termination of a branch with the end of the main axis. 



The thickness of the principal stem measures at the base 9 mm., that of the principal 

 twigs 5 mm. The length of the simple branches varies from 15 to 20 mm. The 

 ccenenchyma is thin and forms, particularly towards the base, but a translucent covering. 

 The polyps are short, conical, 1 to 1'5 mm. high, and 1 mm. in diameter at their base ; 



