. Bulletin of the British Museum (Natural History). 284 AILSA M. CLARK. Fig. 6. a-g. Porphyrocrinus polyarthra sp. nov. a-c. Holotype. a. Distalmost part of the stalk attached to coral (stippled), b. Columnals 59 and 60 from top. c. Calyx with adjacent ossicles, d. Proximal part of loose arm from Brj, showing bases of P3 and Pj. e. Pj (tip missing), f. P9 (tip missing), g. Face of distal synostosial joint from large broken stalk fragment, h. Naumachocrinus liawaiiensis A. H. Clark. Holotype. National Museum cat. no. 29573. Outline of calyx with adjacent ossicles. [The scale equals 5 mm fo
. Bulletin of the British Museum (Natural History). 284 AILSA M. CLARK. Fig. 6. a-g. Porphyrocrinus polyarthra sp. nov. a-c. Holotype. a. Distalmost part of the stalk attached to coral (stippled), b. Columnals 59 and 60 from top. c. Calyx with adjacent ossicles, d. Proximal part of loose arm from Brj, showing bases of P3 and Pj. e. Pj (tip missing), f. P9 (tip missing), g. Face of distal synostosial joint from large broken stalk fragment, h. Naumachocrinus liawaiiensis A. H. Clark. Holotype. National Museum cat. no. 29573. Outline of calyx with adjacent ossicles. [The scale equals 5 mm for a-f and h and 2 mm for g.] The calyx is very slender and slightly constricted at the upper end of the basals, though the radials flare out at the top, this even flaring being continued by the first brachials, which are broader than long. The sutures in the calyx are distinct, those between the basal and radial rings making a zig-zag line. Two detached arms were found in the crinoid debris taken at this station which are very likely to have come from this specimen or the paratype. [Although Democrinus chuni was also collected, its arms differ in tapering from Brg and have the first pinnule on Br^.] The first ossicles on both these two arms have a syzygy on the proximal face and their breadth corresponds with that of the distal end of the first post-radial ossicle still attached to the calyx, so I am fairly confident that they can be regarded as BrjS. They expand to a maximum breadth of 1-5 mm at Brj, having well-marked lateral flanges, and only very slowly taper distally. Both measure c. 40 mm in length. Syzj'gies and muscular joints normally alter- nate from 14-2, 3-1-4 onwards but one of the two arms has extra muscular. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original British Museum (Natural History). Lond
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