220 



BULLETIN 103, UNITED STATES NATIONAL MUSEUM. 



below the Bowden horizon. A recent discovery by Sellards is of 

 importance in determining the age of the Alum Bluff formation.^ 

 The following is a list of the vertebrates: 



Parahijrpus leonensis Sellards. 



Merychippus species. 



Mesocyon? leonensis Sellards, 



Oxydactylus f 



Leptomeryx f 



Sellards says: 



It would seem, therefore, as a whole, that .the vertebrate fossils indicate that the 

 Alum Bluff formation is to be referred to the Miocene. The presence of protohippine 

 horses in particular would seem to be decisive as to the age of the formation, exclud- 

 ing its reference to the Oligocene. 



The opinion of Prof. J. C. Merriam on the age indicated by the 

 MerycMppus is quoted. He says that he would judge the horizon 

 to near the lower portion of the middle Miocene. Later Professor 

 Merriam informed me that he considers the MerycMj^jms as of lower 

 Miocene (Burdigalian) age. 



The evidence in favor of considering the Alum Bluff as of lower 

 Miocene age might be greatly multiphed. The presence at Oak 

 Grove, Yellow River, Florida, of a species of Astrhelia closely related 

 to A. palmata (Goldfuss) of the Maryland Choptank and Calvert 

 formations suggests Miocene. Pecten sayanus Dall indicates Mio- 

 cene. Canu and Bassler are positive that the Bryozoa are of Miocene 

 age. Berry's opinion based on his stud}- of the fossil flora ^ is not 

 incompatible with this interpretation. 



MIDDLE AND SOUTH ATLANTIC STATES. 



The following is a list of the Miocene species, as far as at present 

 known :^ 



Miocene corals from the Middle and South Atlantic States. 



Name. 



Geologic formation. 



Calvert. 



Chop- 

 tank. 



St. 

 Marys. 



York- 

 town. 



Duplin. 



Choctaw- 

 hatchee. 



Paracyathus vaughani Gane 



Astrhelia palmata (Goldfuss) 



Astrangia lineata (Conrad) 



conradi Vaughan 



Septastrea marylandica (Conrad) 



crassa (Tuomey and Holmes). 

 Favites vaughani (Gregory) 



1 Sellards, E. H., Fossil vertebrates from Florida, A new Miocene fauna, Florida Geol. Surv., 8th Ann. 

 Kept., pp. 83-92, 1916. 



2 Berry, E. W., The physical conditions and age indicated by the flora of the Alum Bluff formation, 

 U. S. Geol. Survey Prof. Pap. 98-E, pp. 41-59, pis. 7-10, 1916. 



3 Vaughan, T. W., Anthozoa: Maryland Geol. Survey Miocene, pp. 438-448, pis. 122-129, 1904; The reef 

 coral fauna of Carrizo Creek, Imperial County, California, and its signiflcance, U. S. Geol. Survey Prof. 

 Pap. 98-T., p. 366, 1917. 



