Summary of Conclusions Reached 533 



of plants was effected northward. A reverse and very 

 limited southward migration into Australia then took place 

 also. 



But many genera and even families of ganoids clearly 

 demonstrate that a great North Atlantis land stretched 

 from Europe to N. America. In the lakes and rivers of 

 this great region steady evolution of some of the ganoids 

 there present into higher teleosteans proceeded. But the 

 heavy deposits of Upper Cretaceous marine strata spread 

 over Kansas and adjoining states, with their marine pachy- 

 cormid types of jfish, prove that land oscillation and sea- 

 ward migration of gano-teleosteans had actively begun. 



During Jurassic and Triassic times a great part of the 

 North Atlantis and Eurasian continents must have re- 

 mained intact. Further, finding of species of related genera 

 in Brazil, S. Africa, India, and Australia during Triassic 

 time proves that some connection probably existed between 

 Archenchelis and the East. 



The land masses of Triassic backward to Carboniferous 

 time must have differed greatly in outline from those of 

 today, but a North Atlantis now separate from Angara or 

 a N. E. Asian continent though contemporaneous with a 

 great southern or Gondwana continent, are all proclaimed 

 by the record of fossil fish life as well as other organisms. 



But the most remarkable geographic and geologic 

 revelations that bear on fish life are those in recent years 

 by Arctic explorers. For study of the Carboniferous and 

 Old Red strata clearly prove that from North Pole to 

 South several identical genera lived in rivers or lakes, not 

 the least extensive of which seem to have been in the midst 

 of an Antarctica continent. 



But a much more intimate knowledge of the older 

 Mesozoic and of Palaeozic strata is needed, before we can 

 speak with assurance on the continental and the marine 

 outlines of the early geologic periods. 



