MARYLAND GEOLOGICAL SURVEY cliii 



as they are in America. Ostrea is large and numerous, large Pectens 

 occur, though the latter are perhaps less characteristic of the Miocene 

 than in America. 



The conspicuous place of the Cardiums in our Miocene is hardly filled 

 by the species in the European faunas, where also we find a notable 

 number of Isocardia. Mactra in Europe is represented by Spisula in 

 America. Panopea is about equally conspicuous in both, Cardita more 

 so in Europe, Astarte in America. Corhula and Saxicava, are equally 

 common to both regions. The very characteristic Mytiloconcha occurs 

 in both. A host of uncharacteristic forms, such as Nucnlidce, Ahra, 

 Tellina, Ensis, MacrocaUista, Tim odea, Lima, Phacoides, etc., are com- 

 mon to both, but in Europe Venerupis, Paphia, Eastonia, Lutraria, 

 Cardilia, PecchioUa, Congeria and Adacna are found with no American 

 Miocene equivalents. CrassatelUtes, Crassinella, Agriopoma, Eangia, 

 Mulinia, Melina, occupy the same, or nearly the same, position on the 

 western continent, where the giant species of Venus make their first 

 appearance. 



In a general way, allowing for local peculiarities, the Miocene fauna 

 of North Germany compares well and agrees closely with that of Mary- 

 land, while the Mediterranean Miocene finds a closer analogue in the 

 more tropical fauna of the Duplin beds of the Carolinas. We have not 

 in America any equivalent, faunally, of the Congeria beds of the upper 

 Miocene of Eastern Europe. 



Characteristic Species op North American Miocene. 



Deeming it interesting to know what species, as distinguished from 

 genera, are characteristic of the North American Miocene I have care- 

 fully inspected the lists. By characteristic are meant the species which 

 occur only in the Miocene, and occur in it from top to bottom, or, to 

 exemplify, in the beds from Alum Bluff to Duplin, in the South, or from 

 the Calvert to Yorktown or Suffolk, in Maryland or Virginia. It is 

 not meant that they occur at every horizon or zone, but that they have 

 existed throughout the Miocene somewhere, and disappear with the 

 inauguration of the Pliocene. 



The following list comprises the species so defined, and is to some 



