90 



In general, the lowest bed of the series is a dark greenish-blue 

 mass, composed of clay, fine sand, and a little green sand; while 

 above it, the strata are of various shades, yellow, greenish-gray, and 

 brown. Little uniformity prevails in their arrangement at different 

 localities. 



A thin band of ferruginous gravel frequently overlies the Eocene 

 strata, and forms a distinct line of demarcation between them and the 

 bottom of the Miocene. 



The stratification of the Eocene at various localities is exhibited in 

 detail, and the characteristic fossils specified, while the curious 

 chemical changes which these have undergone, are also discussed. 



Professor Bache presented the printed number of the So- 

 ciety's proceedings for the past three months, No. 6. 



Dr. Hays stated that he had received through a friend some 

 of the vaccine virus, recently obtained by Mr. Estlin, of 

 Bristol, from the cow, and had used it with the most satisfac- 

 tory results. He exhibited a scab, which presented all the 

 characters described by Jenner, as appertaining to the genuine 

 vaccine scab. 



Slated Meeting, April 19. 

 Present, thirty-eight members. 

 Mr. Du Ponceau, President, in the Chair. 

 The following donations were received: — 



FOR THE LIBRARY. 



Memoires de l'Academie Imperiale des Sciences de Saint-Peters- 

 bourg. VIme. Serie. Sciences Mathematiques, Physiques et 

 Naturelles. Vol. IV. Premiere Partie: Sciences Mathema- 

 tiques et Physiques. Vol. II. Parts first and second. St. Peters- 

 burg, 1838. — From the Academy. 



Memoires de l'Academie Imperiale des Sciences de Saint-Peters- 

 bourg. VIme. Serie. Sciences Mathematiques, Physiques et 



