58 PROCEEDINGS OF THE ACADEMY OF [1886. 



and in the most part recognizable only in so far as the determina- 

 tion of genera is concerned. 



The species are referable to the following genera : 



Mysla species probably M. unguUna. 

 Leda species probably L, protexta. 

 Leda species indet. 

 Nucula species probably N. ovula. 

 Turritella species Turritella Mortoni. 



This is, as far as I am aware, the first notification of the dis- 

 covery of marine fossils in the Tertiary deposits of the State. 

 The presence of the strongly carinate form of Turritella Mortoni 

 fixes pretty definitely the horizon, the Lower Eocene, or that of 

 the older Tertiaries of Maryland and Virginia. This is what we 

 should have expected to find from the position of the strata. 



