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Show 116 MB.. C. W. ANDREWS AND OTHERS ON THE [Feb. 20, The shores of Christmas Island are singularly unfavourable for the collection of marine animals ; except in a very few localities, the coast-line is formed by vertical or overhanging cliffs, the base of which is washed by the heavy ocean swell, so that the narrow shelf of fringing reef, which is submerged to a depth varying from a few feet to several fathoms, is unapproachable from the land side, and, except along the north coast in very calm weather, is very difficult of access from a boat. Nevertheless, the examination of this reef and of the submarine slopes of the island between N.E. and N . W . Points, and the collection of their fauna, where possible, would no doubt yield very interesting results, and it might be worth the while of a marine zoologist to spend some time on the island for this purpose. In a few localities on the east coast and at Flying Fish Cove, a narrow reef-flat, like that of an atoll, is exposed at low water, and it is from this in the latter locality that nearly all the specimens mentioned below were obtained. In this place an area about a quarter of a mile long and from fifty to a hundred yards wide is exposed at low tide. Its outer edge forms a slightly raised rim of rocks thickly coated with pink and red calcareous algae, and is cleft here and there by deep narrow channels. Within this raised rim the reef-flat forms a hard concrete-like floor composed of cemented fragments of corals, larger blocks of which lie loose upon its surface. Here and there are shallow pools of water, some of which are choked w-ith thick clumps of small branching Madrepores (e. g., M. clathrata, M. valicla, 31. aspera), the tops of which are exposed to the air for a considerable time between the tides. In some of these pools also there are extensive patches of a pinkish-grey, leathery Alcyonarian (Sarco-phyton). Most of the Corals obtained were from these pools or from the sides of the deeper channels near the edge of the reef. The reef is interrupted near the middle of the bay by a boat-channel with a sandy bottom running up to the beach, and it was from sand taken from about 11 fathoms in this channel that the Foraminifera described by Mr. F. C. Chapman were obtained. The reef-flat seems on the whole rather barren of life. The swiftly running shore-crabs (Grapsns macidatus), which skim over the rocks like leaves driven by the wind, and two Holothurians, the smaller quite black, the larger olive-brown, are the most conspicuous objects. In the pools are numerous small fish, including a little Periophthalmus which jumps from stone to stone with great activity. The Crustaceans and Echinoderms determined by Mr. B. I. Pocock and Prof. Jeffrey Bell are :- Crustaceans :-Actcva nodulosa, Eriphia Icevimanus, Actceodes tomentosus, Lophozozymus sp., Daira perlata, Chlorodius sp., Calcinus elegans, C. tibicen, Aniculus typicus, Stenopus hispidus, Penceus sp.; there is also a large cray-fish which is used for food, but of which unfortunately no specimen was brought back. Echinoderms:-Linckia miliaris, L. diplax, Nardoa tuberculata, |