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Show 1900.] MR. F. P. BEDFORD ON MALAYAN ECHINODERMS. 291 The colour, during life, is bluish green on the abactinal surface, the underside being white (in alcohol the colour rapidly bleaches to a dull grey). This species is distinguished from C. hesperus, the only other known species of the genus, by the spinulation of the inferomarginals and ventrolaterals ; the colour is also probably a constant distinguishing feature. As I hope to publish later some morphological details of this species, I will refrain from discussing here the systematic position of the genus, about which there appears to be much divergence of opinion (cf. Ludwig, Verrill, &c). Arm- No. of E. r. breadth. marginals. Largest specimen.. 75 15 17 47 Smallest „ .. 18 6 6 23 3. ASTROPECTEN JATANICUS, var. MALACCANUS nov. Astropecten javanicus, C. Liitken, Vidensk. Meddel. Naturhist. Foren. 1871, p. 234. Astropecten andersoni, W . P. Sladen, Journ. Linn. Soc, Zool. xxi. 1889, p. 322, pi. 28. figs. 1-4. Reference. C. Ph. Sluiter, Natuurk. Tijd. Ned. Ind. xlviii. 1889. R=3-3xr. Locality 6f Habitat. Abundant in about 2 fathoms on mud, Malacca: their food seems to consist principally of small Lamelli-branchs. Distribution. Previously recorded from Mergui Archipelago and Java. This variety is intermediate between the type and A. andersoni. It differs from the former in the following particulars :-the lateral spines are always sharp; the adambulacral armature is tripla-canthid in adult specimens, the outer series being composed of 2 or 3 small spines forming an oblique arc continuous with the small adoral spine of the middle series. It differs from A. andersoni in the spinulation of the inferomarginals, 3 or 4 spines being developed on each plate and forming a transverse row continuous with the lateral spines at the bases of the arms ; the paxilli have a circular crown with 8 or 9 spines on the periphery and usually a single central spine. The colour is either chocolate-brown or grey in spirit, as in A. andersoni, which seems to me to be a variety of A. javanicus. As in most species of Astropecten, there is a Polian vesicle on each side of the stone-canal and in each of the remaining 4 interradii; each is very long, with a large vesicular extremity, which comes to lie in one of the arms adjacent to the interradius in which the Polian vesicle originates. Arm- No. of R. r. breadth. marginals. 36 11 12 24 or 25 |