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Show 280 MR. F. P. BEDFORD ON MALAYAN ECHINODERMS. [Mar. 20, by Agassiz in the ' Challenger' species of the genus, is the condition of the radial water-vessels ; these, together with the nerves and associated canals, are slung up from the body-wall by a narrow mesenterial fold, so that the nervous system is farther removed from its primitive epithelial position than, so far as I know, occurs in any other Echinoid (see section figured). The division of the nerve-trunk into a deeper and a superficial layer is very obvious in sections, the deeper layer being swollen at intervals on each side to form gauglia: this condition is quite unique among Echinoids, the deeper nerve-layer being absent in the radii of all forms hitherto investigated in which it is said to be confined to the neighbourhood of the oral ring; its occurrence in the radii of this species recalls the condition in Holothurians. In addition to adult examples, of which several were taken, two young stages were obtained which I hope to describe in a later communication in some detail, as they show some important differences in the calycinal system, coronal plates, poison-organs, pedicellarise, &c. I hope also to give a more detailed account of the adult morphology than seemed advisable in a paper dealing chiefly with systematic features. Adult examples seem to average about 83 m m . in diameter and have a height of about 24 mm.; they are thus smaller than the allied species. 4. TEMNOPLEURUS TOREUMATICUS Ag. Temnopleurus toreumaticus Agassiz & Desor, Ann. Sci. Nat. ser. Zool. t. vi. 1846, p. 360. References. Alexander Agassiz, Echini, pt. 3, 1873, p. 463. J. E. Tenison-Woods, Proc. Linn. Soc. N. S. W . vol. iv. p. 159. Locality. Common between tide-marks and up to 5 fathoms on the east of Singapore island; also common in from 1 to 3 fathoms of water at Tanjong Kling near Malacca, and several young specimens were dredged in 10 to 15 fathoms at C. Eachado.' Habitat. At Singapore they are found on Zostera on mud. Distribution. Eeported from the Indo-Pacific area between the Gulf of Persia on the west and New Caledonia on the east ; it extends also into North China, and is recorded from N.E. Australia. The Malacca specimens differ strikingly from those found at Singapore by reason of their much longer spines and somewhat different coloration. In some specimens the general colour-effect is a greenish grey, the spines being light-coloured with 6 to 12 dark transverse bands of the same tint, these bands are conspicuous towards the tip of each spine, but become gradually fainter towards the base; in other individuals the bands are claret-coloured, giving a reddish hue to the entire animal. Individuals do not seem to reach the same size as those recorded from other localities, |