1867.] Natural History of Pratas Island. 147 



except a few insignificant ones, such as Litorinae and Purpura ; 

 nor, though the water was bright and clear, and I waded out 

 as for as I could go, could I anywhere see any traces of Annelids 

 or Echinodernis. The harder parts of the sand were harrowed 

 with deep holes of various sizes, from which emerged from time 

 to time a wary and swift-footed crab (Ocypoda), which scuttled 

 nimbly down to the sea upon the first sign of approaching foot- 

 steps, and appeared to be aware of us at least at 50 yards distance. 

 Nor was it easy to capture a specimen, for while on the one 

 hand they never made the mistake of running away from the 

 sea, on the other hand, if cut off, they fled so quickly, and doubled 

 so nimbly, suddenly running the opposite way without the clumsy 

 process of turning round, that they afforded great amusement and 

 not a little exercise and exertion. 



The sea in the neighbourhood of the Pratas Island has a very 

 variegated appearance, from the alternations of bare white sandy 

 bottom, with patches of Ulva and Zostera, both of which are very 

 abundant. The Ulva is a very beautiful reticulated species, and 

 the Zostera leaves float about in all directions and in all stages of 

 decay, generally bearing upon them minute dendritic polyzoa, 

 lunulites, spirorbis, &c, with which the to wing-net from the ship 

 was replenished. Besides the Ulva, I obtained several other species 

 of seaweed, washed up on the beach, and conspicuous among them 

 a species of Padina, very abundant everywhere in these seas, and a 

 Sargassum. 



As might be expected on so small an island, quadrupeds are 

 scarce, nor did we observe any, though it is said the universal Eat 

 was seen there when the ' Dove ' visited the spot, nor did I notice 

 the bones of any quadrupeds which would have indicated their 

 existence there. The skeletons of turtle I met with more than 

 once, but whether they visit the island, or are cast up dead upon 

 the beach, I am unable to say. No other traces of reptiles were 

 observed. 



Pratas Island is occasionally visited by Chinese fishermen, who 

 repair to it in the early part of the year, and there is a good junk- 

 anchorage in the N.E. corner of the lagoon. We soon came upon 

 traces of such a visit in a clear patch among the scrub, in the midst 

 of which a well had been sunk, from which brackish water might 

 be obtained. There were scattered about various implements of 

 potteiy, in the shape of water-vessels and teapots, some entire and 

 others more or less broken, and surrounding them were strewed 

 great numbers of shells, of a species of Strombus, the remnants of 

 a past feast, and which remained to form a future kitchen-midden 

 in the sand. At the head of the shallow inlet or lagoon stood a 

 joss-house, or Chinese temple, in a rather dilapidated condition from 

 the effects of wind and weather, the roof nearly torn off, and the 



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