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Show 172 MR. CYRIL CROSSLAND ON THE [Mar. 7, R Little previous work 011 the marine fauna of the Islands has been done; indeed, it was difficult to get much information of any sort about the locality*. The ‘ Challenger' spent nineteen days dredging in the harbour of St. Vincent with somewhat discouraging results as regards the Polychfeta and Opisthobranchiata. The former appear to be unusually interesting, however, since, of the fourteen species collected, seven were new and obtained nowhere else, while three were found to be widely distributed in the North Atlantic and West Indies and others were Mediterranean t. The Canary Islands and Madeira have been worked by Langerhans (Polychfeta) and other well-known zoologists. But these Islands are well north of the Tropical zone and afford no fair comparison with the Tropics of the Indian Ocean. 2 . N a r r a t iv e a n d R e s u l t s . In approaching St. Vincent J (text-fig. 22) one is immediately struck by the physical differences between the Cape Verde Islands and the coast of East Africa. In place of the low level lines of the local limestone formation, densely clothed with bush, or, at Zanzibar, with cocoanuts, cloves, and mangoes, we are here confronted with the huge mass of the Island of St. Antonio, 7000 feet in height, rising directly from the sea, with St. Vincent to the left, lower (2400 feet) but even more ragged in outline. Both islands show their volcanic origin very obviously, and their grey precipices and red slopes are utterly devoid of vegetation. The shores themselves, with which we are more directly concerned, also differ. In place of the broad shore-platform, smooth, barren, and almost quite devoid of loose stones, which is characteristic of the East-African coral-rock, we have here a shore, so narrow as to be almost invisible on the Admiralty Charts, composed of lava, and often covered with stones of all sizes, from that of a cottage downwards. The tides rise from 3 to 5 feet at springs, according to the locality, as against 8 to 12 feet in East Africa. In partial correspondence with this the rich zone of the shore in the latter locality is from lowest tide-level down to 2 or 3 fathoms, so that, without wading, little could be done. Here also there is a well-marked l'ich zone, but it extends halfway up to high-water mark and ends abruptly 2 or 3 feet below the level of lowest springs. The rocks of this zone are covered by a belt of mossy green, brown, and red seaweeds and nullipores ; below it they are bare or only merely painted over by nullipore and bear little else * The most useful accounts are in the ‘ Universal Geography,' vols. xi. & xii., and the Admiralty Pilot Series. f ‘ Challenger ' Reports, Summary of Results, vol. i. pp. 303-314. The avian fauna lias been collected for the British Museum by Captain Boyd Alexander, whose results are recorded in the ‘ Ibis,' 1898, pp. 74-118 and 277-285. X Properly the Island is San Vicente, the town Mindello, and the Harbour Porto Grande. For simplicity I use St. Vincent for all three. |