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Show 1900.] MR. F. P. BEDFORD ON MALAYAN ECHINODERMS. 297 Loccditg. This species is fairly common on Pulo Rengkam Singapore, between tide-marks on the reef; it lives in company with, and appears to have a mode of life similar to, the large tropical species of Muelleria. Distribution. This variety has previously beeu recorded from Amboina, Ceram Laut, and the Sandwich Islands. Unfortunately I have only examined one specimen with care, so that I do not know whether the other recorded varieties of the species also occur in the district. This specimen must certainly be regarded as the C. arenosa of Perrier: the pore-areas are not distinct from each other but tend to unite over the whole abactinal surface, leaving small, distinct islands which are devoid of pores and granular, the larger of these spaces being about the same size as the madreporite ; they are devoid of large spines, thus differing from typical arenosa and approaching C. coriacea M. & T. The madreporite is an irregular oval structure, and is quite prominent, being bordered with a few large blunt spines; it measures 13 mm. X 6'5 mm. Dr. Doederlein has shown that C. novce-guinece differs from the Western species C. schmideliana in the character of granulation of the ventrolaterals, the larger granules not being divided up into distinct groups corresponding to the subjacent plates in the former. In the specimen now described this holds good, and parallel to the ambulacral furrow up to within a distance of about 7 mm. from it the granules enlarge gradually up to the furrow, where they form a conspicuous edging; in the adambulacral armature there are 3 to 6 furrow-spines (usually 5) on each plate, the outer row being extremely irregular and poorly developed, over a large part of the arms it seems to disappear completely. Dr. Sluiter has pointed out how impossible it is in this genus to rely on shape for specific diagnosis; and in this species, at any rate, this character depends almost entirely on the mode of preservation. During life, especially when left dry on the reef at low-tide, the outline may alter considerably, and, if placed on a flat surface with the actinal side downwards, the upper side would flatten out over the edge, so that the ambulacral furrow would appear confined to the lower side (cf C. acutispinosa Bell); also when specimens are placed in a basin and spirit is poured over them, the lower surface (abactinal or actinal) will often accommodate itself to the shape of the bottom of the vessel. R -f r = 195 mm. 14. PALMIPES ROSACEPS. Asteriscus rosaceus, Muller & Troschel, System d. Ast. 1842, p. 40 Distribution. Japan and Bay of Bengal. Localitg. One large and rather damaged specimen in 5 fathoms, Singapore. This species, being the only 15-armed Asterinid, is easy to recognize ; it appears to be rare. R sa 121-5 mm., r = 82 mm. |