1847.] Association of Geologists and JVaturalists. 207 



Danube; and the same are found in the rivers of Norway; these 

 could not communicate with each other, and must have been cre- 

 ated in loco. 



On the Cypress of Mississippi and Louisiana, by Dr. Dicker son. 



It has no marked geographical position, except in being near 

 the Mississippi; its latitude is about the same as that of the cot- 

 ton plant. It comprises about one-seventy-fifth of the forests 

 there, and only one-fifth of this is available for useful purposes: 

 much of it is heavier than water, and can therefore not be easily 

 got to market; its growth is very slow; it will probably soon fail. 



It grows in soils completely saturated with water, most of the 

 year, in basin-like depressions, of various heights above the river. 

 Its top ends in a cup-shaped cap; its roots extend to a great dis- 

 tance: from the concentric laminae some have been found which 

 must have been two thousand years old. 



Prof, H. D. Rogers read a report from Lieut. Maury, on the 

 currents of the North Atlantic, which M^ill be of great importance 

 to navigation. Between New York and Havre, and New York 

 and Liverpool, there is only a difference of one day's sailing in 

 distance, while in time there is an average distance of nearly a 

 week. This may be obviated by a knowledge of the currents. 

 In going from Havana to New Orleans, vessels stem a current of 

 three miles an hour against them, when they might have a current 

 in their favor of two miles an hour. 



Evening Session — Thursday, 23d. 



A report was read on the fishes of Lake Winipiseogee, by Dr. 

 Wm. Prescott. Dr. Storer stated that no marine cusk exists in 

 our lakes; what Dr. Prescott described as such, was a lota. 



Prof. Adams made a verbal report on claystone concretions. 

 They are either simple, or compound; binary, ternary, &c. The 

 simple commence by a nucleus, not necessarily a foreign body; 

 around this concentric layers are deposited; these are rare. The 

 complex are made up of two or more simple ones, united laterally, 

 or face to face. The simple ones are modified spheres; in these 

 specimens they are depressed; in the oolitic they are concentric, 

 very perfect spheres; they are caused by the molecular attraction 

 acting in the direction of the radii of a sphere. The kinds of 

 matter subject to this modification are various; carbonate of lime, 

 silex, &c. Each locality has a peculiar type of form. It is easy 

 enough to frame theories of their composition; but none that he 

 knew of explained satisfactorily the phenomena. 



Mr. S. S. Haldemann made some remarks on these concretions; 

 and more particularly on the temperature of the liquid, or semi- 



