GEOLOGY AND PALEONTOLOGY OF THE CANAL ZONE. 



21^ 



15 genera and one subgenus of middle and upper Oligocene corals 

 apparently had become extinct in this region. The genus Thysanus is 

 present in the Pliocene Caloosahatchee marl of Florida ;'and in Santo 

 Domingo Placocyathus, Stylophora, Antillia, and SyzygopJiyllia occur 

 at horizons above that of the Bowdonmarl,jwhile the number of species 

 now living increases. The Bowden marl marks an important change 

 hi the character of the coral faunas, a change from an older to a more 

 recent facies. It therefore seems to me that the Bowden marl can 

 not be considered of OUgocene age, and that it must be referred to 

 tlie lower Miocene. 



SANTO DOMINGO. 



With regard to the species reported by^Duncan from Santo Do- 

 mingo, it will be said that Duncan does not describe the stratigraphy 

 of Santo Domingo, but refers the specimens to the Nivaje shale, the 

 superficial or tufaceous limestone, Posterero shale, Cerro Gordo 

 shales, Esperanza shale, and "the silt of the sandstone plain." The 

 following is a Ust of the species recorded by him, the geologic forma- 

 tion in which they were reported to be found, and the revised names 

 with annotations: 



Fossil corals reported by Duncan from Santo Domingo. 



Name used by Duncan. 



6 



tj CO 



as a 



d 

 "3 



o 



a> 



o 



Ph 



6 

 "3 



J3 

 w 

 03 



1 



1 



m 



•a 



§ a 



Revised names and annota- 

 tions. 















Described from Vera, Jamaica; 





(?) 



+ 











genus doubtful; identifica- 

 tion doubtful. 

 Not determinable. 













Placotrochus lonsdalei Duncan. 













From yellow shale of Angos- 



wards and Haime. 



TrocJiocyafhus laterospinosus M. Edwards 



and Haime. 

 Paracyathus heneTceni (Duncan) Duncan. 



+ 



+ 











tina, Santo Domingo; speci- 

 men not determinable. 

 Placocyathus new species. 









Paracyathus henekeni (Dun- 





+ 









can). 

 Placocyathus barretti Duncan; 





+ 

 + 

 + 



+ 

 + 

 + 







+ 



originally described from 

 Bo-vvden, Jamaica. 

 Placocyathus variabilis Duncan. 











Placocyathus costatus Duncan. 



Pocillopora crassoramosa Duncan 











Pocillopora crassoramosa Dun- 











can. 

 Stylophora affinis Duncan. 













Stylophora minor Duncan. 







1 





Stylophora new species; also 











+ 



from Cerro Gordo shales. 

 Name discarded for Santo Do- 



Haime. 

 Trochocyafhus ahnormalis Duncan 



+ 

 + 



+ 









mingan species. 











iAstcrosmilia abnormalis {Dun- 













can). 













Asterosmilia exarata Duncan; 



Stephanocoenia intersepia M. Edwards 



and Haime. 

 AntUlastraea spon^iformis (Duncan) 



Duncan. 











+ 



+ 



also in Antigua formation, 

 Antigua. 

 1 











\StephaTiocoenia intersepta (Es- 

 J per). 



+ 



+ 







\Dichocoenia tuberosa Duncan. 



Barysmilia inteTmedia Duncan 





+ 





