558 [Feb. 26. 



common in the marine beds, extremely few land and freshwater 

 shells are met with. 



Climate of the Miocene Shells. — Upon the whole, the shells of 

 this formation in Virginia and Maryland resemble those of 

 Touraine and Bordeaux more than the fossils of the Suffolk crag, 

 as we might have expected from their nearer correspondence in lati- 

 tude. Thus, for example, the genera Co7ius, Oliva, Marginella, and 

 CrassaifeZZa (represented by large species), with otherforms of warmer 

 seas, which are wanting in our crag, are common to the miocene 

 beds of Virginia, Maryland, Touraine, and Bordeaux. Yet when 

 we consider that the shelly deposits on the James River, in the 

 United States, are in the 37th degree of north latitude, while the 

 French faluns are in the 47th, we are surprised to see so great an 

 analogy in those characters by which the climate of a conchological 

 fauna may be inferred. The American shells do not seem to in- 

 dicate a more southern latitude by 10°, and the same remark 

 applies equally when we compare the most southern beds of North 

 Carolina with those of Bordeaux. We find in all these localities a 

 great admixture of northern forms, as if the isothermal lines in the 

 climate of the miocene period took a curve to the south when 

 drawn from Europe to America, as they do now. 



Polyparia. — The fossil corals which I observed in different 

 miocene localities were usually few in number, both in species and 

 individuals, with the exception of the Columnaria (f) sex-radiata, 

 which resembles an Astrea, and is very conspicuous, from its size, in 

 the shelly marls near the banks of the James River. The scarcity of 

 these zoophytes may be a local accident, depending on the general 

 rarity of calcareous deposits of this age in the United States. The 

 following is a list of ten species collected by me, and described 

 by Mr. Lonsdale.* 



Miocene Species. Localities. 



1. Columnaria? sex-radiata Lonsdale ( Evergreen, on James River, Virginia ; 



|_ -retersburg, Virginia. 



2. Anthophyllum llneatum Lonsdale Petersburg and Williamsburg, Virginia. 

 (Caryophyllia lineata Conrad) 



3. Astrea hirtolamellata ? Michelin Williamsburg. 



4. Heteropora ? tortilis Lonsdale Petersburg and Williamsburg, Virginia. 



5. Cellepora informata Lonsdale ^Petersburg, Virtrinia. 



6. C. quadrangularis Lonsdale Williamsburg, Evergreen, Virginia. 



7. C. similis Lonsdale Williamsburjr, Virginia. 



8. C. umbilicata Lonsdale Williamsburg, Virginia. 



9. Escharina tumidula Lonsdale Petersburg, Virginia. 

 10. Lunulites denticulata Conrad Williamsburg, Virginia. 



Two species of the above list, namely Anthophyllum lineatum, 

 identical with a Touraine species, and Lunulites denticulata, 

 agreeing with one found in the Suffolk crag and faluns of Tou- 

 raine, correspond with European fossils of the same age. 



With respect to climate, Mr. Lonsdale regards this collection 

 as indicating a temperature exceeding that of the Mediterranean, 



* Vide Quarterly Journal of Geol. Soc. Vol. i. p. 471. 



