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Show 88 ZOOLOGICAL COLLECTIONS MADE DURING [Jan. 4, to find, if possible, some more exceptions to the rule of the presence of four anal plates1; not one, however, was to be found among the fourteen specimens I examined. The localities were :- (1) Portland Bay, 10 fathoms; bottom, hard sand. (2) T o m Bay, 0-30 fms.; bottom, rock, kelp, and mud. (3) Cockle Cove, 2-32 fms.; bottom, mud. (4) Port Rosario, 2-30 fms.; bottom, sand and rock. (5) Trinidad Channel, 30 fms.; bottom, sand. The smaller specimens varied considerably in colour; the light green of the test and the purplish flesh-colour of the spines of the ordinary specimens being in one case replaced by a light brown for both test and spines; one or two examples had reddish patches on the bare spaces of the interambulacral areae ; and in two cases the white pedicellariee, placed on a deep-green test, gave a rarely seen appearance to the specimens; another example had the spines white, with a deep rusty-brown patch in each bare interambulacral space. None of the specimens was of a large size. STRONGYLOCENTROTUSBULLATUS, n.sp. (Plate VIII.figs. 1, 2.) Test rather thick and slightly pentagonal; superiorly to the ambitus the primary tubercles of the interambulacral areae, which are set in two rows, are of considerable size; generally eight pairs of pores in each arc, which is set more or less horizontally, and is separated from the one above and below by a not very regular series of small tubercles; the ambulacral area comparatively narrow; the actinostome moderately small and very faintly notched; abactinal system thickly covered with small tubercles; ocular plates all excluded from the anal system; madreporic body large: anal plates large in size and small in number. Test brownish red; the spines not long, and of a dirty or brownish yellow colour. Straits of Magellan. The difficult genus Strongylocentrotus stands in need of a careful revision; and it is necessary that I should point out some of the reasons which induce me to look upon this species as new, though this is by no means the place to undertake any thing like a general review of the group. It seems, then, to be the only species in which all the ocular plates are excluded from the anal system-presenting a considerable resemblance to S. franciscanus, in so far that the primary tubercles of the interambulacral areae form, in both species, two rows, and are considerably larger than any others on the test; it is distinguished not only by having the tubercles absolutely smaller, but also by the fact that it is above rather than at the ambitus that the largest tubercles are to be found. So, again, a resemblance is to be seen to S. albus in the presence of tubercles separating the 1 P. Z. S. 1879, pt. iii. p. 436. I may here state that during the autumn of 18791 took the opportunity to examine the few specimens of this genus that are deposited in the Natural-History Museum at Brussels; but I was not able to detect in any of them any indications as to the presence of more than four |