Report on the zoological collections made in the Indo-Pacific Ocean ...

;ECHINODEKMATA. 1574. Antedon carpenter!. (Plate X. figs. A, a-c.)Centrodorsal a flattened disk ; about 12 marginal cirri, of almost20 short joints, of which tlie lowest are almost twice as broad asthey are long ; it is not till we reach the penultimate one that wesee a distinct spine, though the dorsal surface of most of them isproduced into a minute protuberance.First radials not visible ; the second do not or do only slightlytouch, united to the third by ligament. Ten arms. First brachialstouch, they are nearly oblong and more than twice as wide as long ;the second are a little wider on their outer than their inner sidethe third with a syzygy ; fourth to sixth oblong, seventh wider oninner than outer side, eighth wider on their outer than inner, andso on alternately ; twelfth and thirteenth serrated at their distaledge ; the fourteenth syzygial. Thence from four to seven jointsbetween each syzygy. 130-180 joints in the arm.The second pinnules on the fourth brachial are very stout, withextraordinarily wide joints, which are armed on either side byspinous projections ; the first pinnule is a little longer than thethird.Colour white, with purple bands or patches, not always developedat the syzygies. The middle line of the arm often white.Arm about 40 millim. long, disk 6 millim. in diameter, cirri lessthan 9 millim. long.This species has some considerable resemblances to A. serripimia,from which, however, the pinnules alone would, as Mr. Carpenterassures me, be sufiicient to distinguish it.Port Curtis.5. Antedon pumila. (Plate X. figs. B, a-h.)Centrodorsal rather wide, rounded ; with about 25 cirri, in threerows, very delicate, of about 12 joints, which, from the fourth onward,are a good deal longer than broad, hourglass-shaped, but a little widerat their distal than at their proximal ends ; some are also producedinto a small spinous ventral process ; no dorsal spine developed tillthe penultimate, and that is small.First radials just visible, second not in contact ; axillaries triangularin shape, sloping backwards in the middle line. Ten arms.First brachial longer without than within, the second within thanwithout and projecting backwards in the middle line ; the thirda syzygy wider within than without. The succeeding jointsmay be incised, so as to leave a lozenge-shaped space betweenevery two ; when this disappears, the joints which have projectedstrongly forwards on either side alternately become more evenlyoblong.Syzygies 3,