Australian Natural History. ♦ 1475 



being then about nine feet On such occasions, when the sea is pretty 

 smooth, one may walk to the verge of the reef in any part, and closely 

 observe the numerous species of coral which there flourish in great 

 beauty and vigour. The margin is very irregular, generally over- 

 hanging, intersected with small channels and deep winding recesses 

 fringed with massive and branching corals. In many places the sur- 

 face is found to be a mere shell or crust, the roof of cavernous excava- 

 tions communicating outwardly with the surrounding w r aters, and occa- 

 sionally also with the surface of the reef, by small apertures or blow- 

 holes, through which the water boils up at each heave of the sea. 

 Outside, the base of the reef slopes very suddenly, probably at an an- 

 gle of not less than 45° ; there is consequently no anchorage for 

 large vessels under the lee. On one occasion, H. M. Sch. Bramble, 

 whilst holding on to the reef by a kedge and two hawsers on end, 

 sounded in 350 fathoms, and no bottom was ever obtained at a greater 

 distance (to seaward) off the reef, than a quarter of a mile. The body 

 of the reef is nearly a dead level, strewed over with large, flat, loose 

 masses of coral, generally partially immersed in shallow pools left by the 

 tide, with occasional accumulations of fragments of corals, dead shells, 

 san*d, and other detritus. Several species of Alcyonium clothe the 

 stones with their sponge-like slippery expansions of various colours, 

 chiefly green. The Algae on the reef are few in number, consisting 

 chiefly of delicate confervoid species. 



Of the Botany of the islet I can give but a very meagre account, for 

 a collection of about twenty species, found by me, unfortunately went 

 to decay for want of a proper place of stowage on board ship. Several 

 of these species I have elsewhere observed on the main land of New 

 Holland; among others, a long, trailing, woody plant, with con- 

 spicuous yellow blossoms, and a large white-flowered Convolvulus. 

 Two species, very abundant, on the island, were used by us as vegeta- 

 bles, one of them under the name of spinach, for which it was consi- 

 dered a very fair substitute, and as such served out to the ship's com- 

 pany. Most of the plants of the island are more or less succulent : 

 there is but one shrub, a slender Acacia, five or six feet high, with 

 small yellow flowers. 



No Mammalia were observed upon Raine's Islet, but we found not 

 less than eighteen species of birds, several of which were new to sci- 

 ence, inhabiting this mere speck of land, and to me they constituted 

 the most interesting feature of the place. Upon nearing the shore on 

 my first visit in May, 1844, an immense cloud of sea-fowl was ob- 

 served hovering over the place, and their cries were distinctly heard at 





