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



Antipathella ? speciosa, n. sp. (PL II. figs. 5-7). 



Corallum consisting of several very large flabellate fronds springing from a strong 

 basal framework. The main divisions of each frond are chiefly in one plane, but in dry 

 specimens the surface may be undulating, and the margins of the smaller fronds are 

 gracefully incurved. A large number of short pinnate branchlets project subvertically 

 from the anterior surface of the corallum, and are not included in the general 

 reticulum. 



The largest fan-like frond measures 1 m. in height; it is only about 12 cm. broad 

 at the base, but rapidly spreads out so as to be over 1 m. broad near the apex. 

 The lower portion consists of a number of radiating branches, 3 to 6 mm. in diameter, 

 which have a very irregular course. These are connected together by bridges of 

 sclerenchyma at frequent intervals, forming an irregular reticulum, the meshes of 

 which are filled in with slender pinnate branches. Branches 3 to 4 mm. in diameter 

 reach halfway up the colony, but the lower ones often taper away to smaller branches 

 after a course of 18 to 30 cm., and give rise to others which become thickened 

 some distance from their origin, and so continue the stronger portions of the axis to a 

 greater height. About 20 cm. from the apex of the corallum the branches are 1 to 

 2 mm. in diameter, being usually much compressed laterally. These give rise to a 

 number of branchlets at irregular intervals, which are 6 to 10 cm. long and mostly take 

 a subvertical course. The derivatives of five of these branchlets may occupy 14 or 

 15 cm. in the breadth of the corallum. Each branchlet bears a large number of sub- 

 alternate slender pinnules, eight or nine of which may be distributed to each centimetre 

 in length. Most are about 1 cm. long and simple, and though chiefly lateral are 

 certainly not always so. At intervals of 0"5 to l - 5 cm. a pinnule becomes elongated and 

 alternately pinnate, and may reach a length of 4 cm. without showing any considerable 

 increase in thickness. The pinnules of adjoining branchlets become fused with one 

 another quite close to the apex of the corallum (PI. II. figs. 5, 6). 



The spines are similar in shape to those of Antipathella minor, but are larger and 

 more pointed. A spiral arrangement is not marked, but the spines are arranged in 

 regular longitudinal rows, five of which may be counted from one aspect of a pinnule. 

 The members of a row are from two to two and a half lengths apart (PI. II. fig. 7). 



The specimen is dry and the whole corallum is covered with a thin brown semi- 

 transparent film soluble in caustic potash, the presence of which has made it impossible 

 to give a good figure of the specimen. Apparently, no polyps remain even as small 

 rounded prominences along the pinnules, such as may be observed frequently in dry 

 specimens. It is difficult to understand how such a continuous brown film has been 

 produced. Nothing of a similar nature has come under my notice in other specimens. 

 So far as I can ascertain the specimen when obtained was completely covered with a 



