AEQUINOCTIA, AN OLD PALEOZOIC CONTINENT 575 



surrounded by a sandy argillaceous formation of red color in the 

 north and yellow in the east. 



Patches of Carboniferous limestone occur more abundantly 

 as we approach the Cordilleras of Annam, on the east coast. 

 Suess mentions (Vol. Ill, Part i, p. 297) that Bell crossed these 

 Cordilleras in a westerly direction, starting from Tourane (on the 

 eastern coast of Annam, by latitude i6°io'N.). They appear to 

 be composed of various zones, first of dioritic and granitic rocks,, 

 then of gneiss and crystalline schists, and lastly of rather recent 

 formations (Vol. II, p. 275, and Vol. Ill, Part i, p. 297). The 

 granitic rocks advance toward the south, along the coast, from 

 latitude i4°N. to Cape St. Jacques, southeast of Saigon, and they 

 must be the southern extremity of a very long mountain chain 

 stretching in a northern direction to the granite highland of Laos 

 (Vol. II, p. 275). 



In this way we come back to the old low massif of Cambodge 

 and to the delta of the Mekong, in Cochin-China. 



Like Australia to the southeast, Cochin-China and Tonkin 

 constitute very old uplands (Suess, Vol. I, p. 607) to the northwest 

 of the East Indian Archipelago. 'Between these uplands we have 

 the granite massifs of southwest Borneo, which separate the folds 

 of the eastern part of this island into two zones, one extending 

 toward the west and the other toward the south, the massifs of 

 granite, gneiss, and crystalline schists of Central Celebes and the 

 horsts of Boeroe and Ceram which, together with others, are 

 probably part of an old massif (Suess, Vol. Ill, Part 3, p. 1036). 



It is only southward from latitude 22°S., along the eastern coast 

 of Australia on one side, and northward from the Shan states, 

 North Annam, and Yun Nan on the other side, that the Silurian and 

 Devonian appear. , Then, on the northern side, more to the north, 

 exists the Cambrian and the pre-Cambrian beneath. The latter 

 plays an important part to the south, but still more north of the 

 Tsing-ling-chan in China. On the southern side (viz., in Australia), 

 however, these last-mentioned two formations do not appear. 



In the intermediate territory, to which the archipelago belongs, 

 outcrops of old crystalline schists occur in many places, but no 

 explorer has discovered any fossils of the Old Paleozoic. 



