456 C. SCHUCHERT PALEOGEOGRAPHY OF XORTH AMERICA 



Mexico-Caribbean mediterraneans. — These mediterraneans appear to be 

 of very ancient origin ; the former certainly existed previous to the Cam- 

 bric. There is today free communication between them by way of the 

 Yucatan channel, which may not have been the case throughout the Paleo- 

 zoic. The Caribbean may have occurred as a deep-sea extension of the 

 Pacific, land locked in the east, and stretching across Costa Pica and Pan- 

 ama during the Paleozoic and Mesozoic, with overlaps across northern 

 Archiguiana. Its Atlantic, or Poseidon, connections across Antillia 

 (lesser Antilles) were established either late in Mesozoic or early in Cen- 

 ozoic times. 



Throughout most of the Paleozoic the Mexico mediterranean was in 

 open communication with the Mississippian sea by way of the Mexico- 

 embay me nt. The Mexican gulf "once stretched to the Arctic sea," and 

 was "in early time but the deeper part of the continental ocean 7 ' (Dana, 

 1856, 345). It connected with the Pacific by way of the Sea of Tehuan- 

 tepec certainly in the Siluric and Pennsylvania and probably also in the 

 Devonic. During Mesozoic times Mexico and the Gulf states were widely 

 inundated by the gulf, although this submergence was less in the Tertiary. 

 The Paleozoic faunas of the Gulf of Mexico greatly affected the life of 

 the Mississippian sea, with its decided South American connections which 

 spread north along the western side of Archiguiana. The faunas in the 

 Mesozoic, however, were Atlantic and agree best with those of southern 

 Europe, though additions at times appear from western South America. 



Antillia. seems to have been submerged for the first time by the Mexico- 

 Caribbean mediterranean late in the Mesozoic, and thus remained during 

 the Eocene and Oligocene, when this region is represented by one vast 

 ocean with a few small islands. 



Mexico embay ment. — See Mississippian sea. 



Mississippian sea. — This vast Paleozoic continental sea was first defined 

 by Dana 59 as "the Central interior or Mississippi basin," but later was 

 changed by "Walcott 60 to "Mississippian sea." 



This shallow Paleozoic sea variously occupied more or less of the Missis- 

 sippi and Ohio drainage areas, and was usually in free communication 

 with the Appalachian sea. During Ordovicic and Siluric times it was also 

 in open connection with the Hudson and Cordilleran seas, but after the 

 Siluric only occasionally with the latter area. The chief and most per- 

 sistent source of its waters and faunas was the Mexico mediterranean, and 

 secondarily the Atlantic (= Poseidon) by way of the Appalachian sea. 



59 Dana : Bull. Geological Society of America, vol. 1, 1890, p. 41. 



60 Walcott : Proc. American Association for the Advancement of Science, 1894, p. 144,- 

 with map. Also see Ulrich and Schuchert, Rep. New York State Paleontologist, 1902. 

 pp. 636, 660. 



