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Show 1882.] MR. S. O. RIDLEY ON THE CORALLIIDJ3. 225 belong to Corallium s. str., and is perhaps identical with C. nobile (see below, p. 232). In C. beckii the branches anastomose and are terminally dilated, both of which are characters quite wanting (as constant characters) in C. nobile as in all other known species; its systematic position in the family is quite uncertain. 1 will now proceed to describe, first, the new species, and next the form which I have said is probably distinct, and then give a table showing the arrangement which these additions to our knowledge seem to render necessary. I will conclude with some remarks on the family and its allies, and some further notes on the fossil forms. CORALLIUM STYLASTEROIDES, sp. nov. (Plate IX. figs. 1-4). Normally branching in one plane. Stem stout, irregular in transverse section. Branching luxuriant, apparently normally dicho-tomous, but subject to considerable variation. Branches tortuous, decidedly compressed laterally in the case of all but the peripheral members, arising from the antero-lateral rather than the posterolateral aspects of the stem or branches from which they may be derived, diminishing gradually in thickness towards the peripheral part. A few small branchlets are scattered on sides of the larger branches irregularly, and are, together with the terminal branchlets, generally subclavate in form, consisting of a slightly contracted basal portion and an enlarged, pointed, and polyhedric terminal portion. Posterior aspect of main branches very convex, of lesser branches less so. Axis of corallum hard, compact, but perforated by a few canals (normal, or due to parasites?) of about 1 m m . diameter, which issue distally at various points on the lateral aspects of the branches, the openings being often covered by a curved lamina of hard material; colour pure white throughout. Longitudinal striae of surface fine, about four to 1 mm.; grooves for polypes generally with a narrow raised lip on each side; length of grooves 1*5 to 2 m m . long (in direction of branches) by about *75 m m . broad, and about *5 m m . deep in the centre, which consists of a smooth-walled hemispherical pit. Surface of hard axis covered by a very thin spicular cortex, which does not conceal the subjacent striae; it is beset with minute projecting points (visible only with the aid of a lens) arranged along the striae of the hard axis ; colour of cortex extremely pale orange. Verrucae placed in the grooves above mentioned, not projecting beyond their margins, or in slight depressions distributed over all parts of the corallum, but most abundantly on the lateral aspects of the main branches, and on the small terminal and lateral projecting branchlets ; their peripheral part consists of a pale pink collar, slightly darker than the general crust; the eight valves are very pale yellow in colour, actual diameter about •75 mm. Spicules of cortex of one kind only, viz. small, cylindrical, with one terminal tubercle at each end, and a whorl of 3 tubercles surrounding each end, and leaving a slight median space usually bare of tubercles ; the tubercles are broad and truncate, the ends bearing P R O C ZOOL. Soc-1882, No. XV. 15 |
