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Show 282 PROF. BELL ON N E W SPECIES OF OPHIURIDS. [May 15 where tbe arms are proportionately longer, the disk swollen, and accessory mouth-shield double or triple, and the colour is very different ; but it may be of some significance to observe that that species is from the not distant shores of N e w Zealand. 2. PECTINURA CAPENSIS, sp. nov. (Plate XVI. figs. 3, 4.) Beneath the superficial granulation of the disk are well-marked, somewhat swollen plates ; there are no pores between the arm-joints ; the radial shields are naked; there are ordinarily five short arm-spines and two tentacle-scales. There are two representatives of this well-marked species, but, unfortunately, none of the arms are complete. The disk does not appear to be puffed or swollen, and its diameter is probably about one fifth the length of the arms ; there is a slight ridge to the arms. There are seven or eight mouth-papillae; the outermost is very small, the penultimate very large ; the mouth-shields are triangularly cordiform, the sides faintly notched, the accessory mouth-shields small and sometimes divided. The upper arm-plates are encroached upon by the side-plates in such a way that their lateral margins are acutely angulated, and the plates are wider in their middle than along either the proximal or distal edge ; the side arm-plates are a little swollen and projecting, and ordinarily carry five short spines ; the under arm-plates have the distal edge, which is concave adorally, nearly twice as long as the proximal; the sides are excavated by the two tentacle-scales, the inner of which is obscured by lying behind the lowest spine. The naked radial shields are rather small, irregularly pyriform. There is very little difference between the rather coarse granulation of the upper and lower surfaces of the disk. The dried specimens are yellowish in colour; darker bands extending over four or five joints of the arm are separated from one another by about five more lightly coloured joints. Diam. of disk 10 m m. Hab. Cape of Good Hope ; in coll. B.M. According to the arrangement of Mr. Lyman (' Challenger Report,' p. 14), this new species stands between Pectinura infemails, in which there are nine, and P. heros, in which there are three arm-spines. 3. OPHIOPEZA ASSIMILIS, sp. nov. (Plate XVI. fig. 5.) A species very closely allied to, but apparently distinct from, O. con-jungens, Bell; thus the arms are not carinated, are more, not less, than four times the diameter of the disk, the granulation of the disk is coarser, the radial arm-shields are less prominent, the mouth-shield is of a somewhat different contour, and the arm-spines are subequal. I must confess that had this specimen come from Torres Straits instead of Port Jackson, I should have greater hesitation in regarding it as representative of a distinct species-great as the hesitation has been. But the differences between the fauna of Port Jackson and Torres Straits are, as we are now beginning to recognize generally, so considerable that the difference in habitat together with the number of |