THE QUARTEELY 



JOURNAL OF SCIENCE 



APKIL, 1867. 



I. THE NATUEAL HISTOEY OF PEATAS ISLAND, IN 

 THE CHINA SEA. 



By Dr. Cuthbeet Collingwood,* Naturalist on board of 

 H.M.S. < Serpent.' 



Pratas Island is situated in lat. 20° 42' N, and long. 116° 43' E., 

 and is of a horse-shoe shape, occupying the centre of the sunken or 

 western part of the great Pratas reef. The reef itself is of a 

 crescentic form, extending 13 miles to the eastward, and having a 

 breadth from north to south of 12 miles, encloses a lagoon of about 

 10 miles in diameter, dotted over with numberless coral patches and 

 shoals. It lies in the direct line of route between Manilla and 

 Hong Kong, and is therefore a spot where many a good ship has 

 been wrecked, especially upon its south-eastern side, which is too 

 often concealed by the thick fogs which prevail during the N.E. 

 monsoon. The Pratas reef and island were surveyed by H.M.S. 

 ' Saracen,' J. Eichards master commanding, in 1858, and at that 

 time it was believed that vessels of 15 feet draught could enter the 

 lagoon by the south channel, between the south side of the island 

 and the south-west horn of the reef, but in our recent visit in 

 H.M.S. ' Serpent,' Commander Bullock found that although only 

 drawing 12 J feet, she could not safely make the attempt, to my 

 great disappointment, and consequently she was anchored on the 

 edge of the reef, 3 miles south of the island, which thus sheltered 

 the ship from the strong N.E. wind blowing at the time. 



Pratas Island is about a mile and a half long, and half-a-mile 

 wide, and is only visible at a distance of 8 or 9 miles in clear 



* It may be interesting to our readers to know tliat the author of the above 

 article gave up his occupations in Liverpool about a year since, and volunteered as 

 naturalist on board one of H.M.'s surveying ships in the China Seas. 



His friends will be glad to hear that in December last he was at Singapore, from 

 which place he sent us the present article, and was about to proceed to Labuan, 

 Sarawak, &c. — The Editors. 



vol. rv. L 



