. Bulletin of the British Museum (Natural History). 126 AILSA M. CLARK Description. The larger specimen has arms 40 + c- 5 Tim long and the breadth at the first syzygy, 3 + 4, is i-2 mm. The very thick discoidal centrodorsal is i-i mm high and 2-4 mm in maximum diameter; the diameter of the flat but markedly spinose dorsal pole is 1-7 mm. The cirri number XII; the three remaining have 33. 33 a-nd 35 segments; the last measures i2-o mm in length. The longest cirrus segment, about the eighth, has length ; median breadth 0-55 : o-6o mm with maximum breadth 0-65 mm including the dorsal projection.
. Bulletin of the British Museum (Natural History). 126 AILSA M. CLARK Description. The larger specimen has arms 40 + c- 5 Tim long and the breadth at the first syzygy, 3 + 4, is i-2 mm. The very thick discoidal centrodorsal is i-i mm high and 2-4 mm in maximum diameter; the diameter of the flat but markedly spinose dorsal pole is 1-7 mm. The cirri number XII; the three remaining have 33. 33 a-nd 35 segments; the last measures i2-o mm in length. The longest cirrus segment, about the eighth, has length ; median breadth 0-55 : o-6o mm with maximum breadth 0-65 mm including the dorsal projection. This projection takes the form of a single distally directed spine from about the twelfth segment measuring up to c. o-i mm in height but on several segments preceding the twelfth there is an additional slightly smaller spine each side making a transverse row of three. Pi has 10 or 11 segments and measures c. 2-6 mm. Po with 12 segments is c. 4-0 mm long and P3 with 10 segments 3-4 mm long. P2 and the following pinnules have markedly spinose and flared distal ends to the segments after the basal two and are distinctly prismatic in their distal halves. Pa is absent throughout and Pi on one arm. The smaller specimen has arms c. 35 mm long; the breadth at the first syzygy is 1-05 mm. There are 30 segments in two mature cirri counted. The dorsal spines are sharper and more prolonged than in the other specimen (see fig. 13c) and are usually single from the tenth segment, being preceded on several segments by a transverse ridge of three Fig. 13. Coiylometra gracilicirra (A. H. Clark). 'Anton Bruun' st. 18A, N Malacca Strait. Arm br 1-2 mm (after IIBr series), a. side view of proximal part of an external arm from Br2 to Br? showing Pi to P3; side view of calyx, bases of poEt-radial series and a cirrus; c. dorsal view of cirrus segments 8-11 of smaller specimen showing transition from small multiple spines to single large one; d. side view of segment 12 and e. of cirrus tip.
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Keywords: ., 1973, boo, bookauthorbritishmuseumnaturalhistory, bookcentury1900
