io8 Temper at tire Sections Surveyed. 



terranean, the most remarkable illustration of the conditions of 

 temperature in a nearly land-locked basin. The two soundings 

 of Station 202 and Station 211 were obtained at an interval of 

 three months, the former in October, 1874, the latter in January, 

 1875. On both occasions the decrease of temperature ceased at a 

 depth of 400 fathoms, and remained stationary at io°.2 C. from 

 that level down to the bottom. It will be remembered that the 

 temperature of the Mediterranean was found by H.M.S. " Porcu- 

 pine" to remain stationary from 100 fathoms downwards. 



The Philippine Inland Seas. — The high bottom-tem- 

 peratures observed in these seas prove that, like the Sulu Sea, 

 they are virtually inland basins, and do not communicate with 

 the China Sea in the west and with the Pacific in the east by 

 channels deeper than 150 or 200 fathoms. 



The China Sea. — This sea also forms a nearly land-locked 

 basin. Its greatest depths as yet ascertained are situated in the 

 north-eastern portion, near the island of Luzon. The obser- 

 vations made at Station 205 and Station 206 are about two 

 months apart, which may account for the comparatively higher 

 temperatures of Station 205. A typhoon had swept these seas 

 in the interval. The decrease of temperature is arrested at a 

 depth of about 1000 fathoms, below which the temperature of 

 the water remains at 2°.4 C. down to 2100 fathoms. This low 

 temperature shows that the China Sea communicates with the 

 Pacific by channels of considerable depth, probably situated 

 between Formosa and Luzon. 



The Sea of Papua. — Only the western portion of this large 

 basin, which extends from the Philippines to the Fiji Islands, 

 has as yet been explored — by the " Challenger " in February and 

 March, 1875, an< ^ by the- " Gazelle" in the course of June and July 

 of the same year. The sections from Mindanao to the Admiralty 

 Islands (Plate 16), and from the latter to Station 224 (Plate 17, 

 Tables X. and XL), represent the temperature-observations made 



