

IIES 



en 

 > 



<o 



co 



2 



IES 



CO 



O 



Z 



> 

 2 



Z 

 CO 



c 

 H 



o 



z 



co 



z 



z 

 .< 



: z 

 o 



CO 



X 



Es"s 



CO 

 UJ 



q: 



<; 



o: 

 oq 



a? 



> 



JO 



m 

 co 



I ES Si 



co 



1/ 



> 



z 

 co 



34 CONTRIBUTION TO THE PALEONTOLOGY OF TRINIDAD. 



A second hypothetical route lay further south and connected the southern 

 part of South America with South Africa. This is thought to have been formed 

 by a northern extension of Antarctica. A strong argument in favor of this is 

 that the present floor of the ocean shows in that region a plateau-like elevation. 



As regards the hypothetical eastern lands lying off South America we find 

 ourselves in a dilemma: our knowledge of continental growth indicates that the 

 lands and seas have not changed places to any great extent; yet we are con- 

 fronted by indirect evidence of the existence of such a land mass, — first by the 

 necessity of a pre-existing mass to supply the rock debris for building up 

 the oldest known rocks of northern South America, and second by certain faunal 

 relations with the eastern hemisphere. 



Messrs. Katzer, Guppy, Jukes-Brown and Harrison, from examinations of the 

 order of deposition of the rock formations of Brazil, Trinidad and Barbados, 

 agree in the conclusion that the material composing the oldest rocks in those 

 areas were furnished by a former land extending to the eastward and northeast- 

 ward (virtually Atlantis). This is thought to have existed during the Cretaceous 

 and early Tertiary times, then to have been gradually submerged, disappearing 

 beneath the sea in the mid-Tertiary. The crystalline highlands of Guiana and 

 Brazil are looked upon as originally the western end of this vanished continent 

 of which they now constitute the isolated ruins. 



But, as above noted, several of the greatest depths of the Atlantic now overlie 

 this supposed sunken continent. It is, however, true that the occurrence of 

 Foraminiferal beds in the southern Antilles, containing genera now found living 

 at great depths, shows that very unusual changes of level have taken place there, 

 and it may be that the normal standards of continental stability cannot be 

 applied in that area. 



As regards the South American faunal relations, the discovery of a basal 

 Eocene formation on Soldado Rock containing fossils some of which are common 

 to the southern United States and to Brazil,— joined with Dr. Heilprin's and Dr. 

 Dall's earlier discoveries of the relationship of the Antillean with the Floridian 

 Oligocene— has awakened the writer's belief that the affinities of the Tertiary 

 faunas of South America are far stronger with North America than, as was pre- 

 viously supposed, with the Old World. 



From the recent to the early Paleozoic the following faunal resemblances are 

 indicated between the Americas. 



But it is true that certain very interesting relationships also exist between 

 the faunas of South America and the Eastern hemisphere. The most striking 

 instances are (1) the well known Devonian Leptoccelia flabellites fauna which not 

 only is common to North and South America, but is also found on the Falkland 

 Islands and in South Africa; (2) the famous Glossopteris flora of the Carbonifer- 

 ous; and (3) the Cretaceous Ammonitic fauna of which the typically South 

 American genus Pulchellia has been traced by Douville and others through the 

 Alps as far east as Roumania and even into Asia. These pelagic forms were 



J I NV 



SMI 



