376 



SCIENCE 



[Vol. V., No. 118., 



rather large possible errors of the results of such ex- 

 periments; and for that purpose I used the material 

 nearest at hand. In order, however, to prevent any 

 further misapprehension, I desire to say that I fully 

 concede Dr. Sturtevant's claim to priority; although, 

 owing to the fact that the bulletins of the New-York 

 station are to be had at first hand only through the 

 press of that state, I was not aware, at the time my 

 results were first published (Bulletin No. 3 of the 

 agricultural experiment-station of the University of 

 Wisconsin, June, 1884), that he had anticipated me 

 by three or four weeks. 



I fully appreciate his remarks regarding the value 

 of recognition, on the part of science, of scientific 

 work at experiment-stations, and should regret ex- 

 ceedingly to seem to fail of doing whatever in me 

 lies to secure such recognition. The field of agri- 

 cultural science is too wide, and the workers in it 

 far too few, to justify any professional jealousy. 



H. P. Armsby. 



Madison, Wis., April 30. 



Tertiary phosphates in Alabama. 



Since the publication of my two notes in Science 

 last year, respecting the occurrence of phosphates in 

 the cretaceous formation of this state, we have found 

 that they occur also at at least two distinct horizons 

 in the tertiary formation. 



This formation in Alabama shows the following 

 well-marked subdivisions, given in descending or- 

 der: — 



also on the Alabama River, at Gullette's and Black's 

 Bluffs, and crops out between the two rivers in the, 

 lower part of Marengo county, where its presence is 

 indicated by limy, spots, or 'prairies,' of very great, 

 fertility. This marl contains also a very considerable 

 percentage of greensand, and, apart from the phos- 

 phoric acid which it contains, would have become a 

 valuable fertilizer. 



The other phosphate-bearing horizon is in the lower 

 or Jackson division of the white limestone. 



At the base of the orbitoidal limestone which 

 forms the greater part of the bluff at St. Stephen's, 

 Mr. Langdon finds a hard ledge of rock holding 

 Plagiostoma dumosa, and immediately beneath this, 

 and extending fifteen feet down to the water's edge, 

 a glauconitic marl holding numerous nodules or 

 concretionary masses of phosphate of lime, — an occur- 

 rence quite similar to that of the nodules in the cre- 

 taceous beds at Hamburg in Perry county, described 

 last year. Mr. Langdon' s analysis of the greensand 

 marl holding the nodules shows 0.6% of phosphoric 

 acid, while a sample of the nodules analyzed con- 

 tains 22.68% of phosphoric acid. 



On the opposite side of the river, in Clarke county, 

 similar materials have been collected and analyzed. 

 A greenish glauconitic sand, occurring some three or 

 four miles north of Coffeeville, contains 1.76 % of 

 phosphoric acid. 



Fifteen or twenty feet above this marl, there is a 

 yellowish-brown loam holding soft yellow nodular 

 masses varying in size from one inch to eighteen 

 inches in diameter, and containing 2.74% of phos- 

 phoric acid. This loam is probably formed by the 

 disintegration of the Jackson limestone, the age of 



Vicksburg 175 (?) feet, 



Jackson 60 " 



Claiborne 150 " 



Bubrstone .... 175-200 

 Lignitic 1,000 



White limestone of Tuomey Oligocene. 



Claiborne, 



Calcareous Claiborne of Hilgard, 1 



Siliceous Claiborne of Hilgard, 

 Lignitic and flatwoods of Hilgard, 



Eocene. 



The upper of these two divisions consists mainly of 

 limestones, called throughout the country, and by 

 Professor Tuomey, the ' white limestone.' 



The lower division consists of sands and clays, 

 which make up the greater proportion of the thou- 

 sand feet or more of the strata of this group ; but in- 

 terstratified with these are five or six, and perhaps a 

 greater number, of beds holding marine shells, the 

 aggregate thickness of which may perhaps be given 

 at a hundred feet. 



Mr. D. W. Langdon, jun., of the state geological 

 survey, while on a collecting tour for Mr. T. H. Al- 

 drich, made the discoveries to which this note is in- 

 tended to call attention. 



At Nanafalia, on the Tombigbee River, there is a 

 remarkable series of beds, over fifty feet in thickness, 

 made up almost entirely of the shells of a small 

 oyster (Gryphaea thirsae). At intervals throughout 

 this thickness are projecting indurated ledges, hold- 

 ing the same shells, but forming a tolerably compact 

 rock. A specimen from one of these hard ledges, 

 one or two feet thick, has been analyzed by Mr. 

 Langdon, and found to contain 6.7 % of phosphoric 

 acid. Other parts of the Gryphaea beds may be 

 similarly phosphatic, but no analyses have yet been 

 made to show it. 



This Nanafalia marl, which occupies a position 

 nearly in the centre of the lignitic subdivision, occurs 



the stratum being indicated by the specimen of Plagi- 

 ostoma dumosa which it contains. 



Again : near Grove Hill, in Clarke county, one of 

 my students, Mr. S. S. Pugh, has collected a number 

 of phosphatic nodules which contain 19.48 % of phos- 

 phoric acid. 



Where the argillaceous limestones of the Jackson 

 age form the surface, they give rise, in their disinte- 

 gration, to the rich limy or ' prairie ' soils which 

 characterize my 'Lime Hills' region, 1 which occurs 

 over a good part of the counties of Choctaw, Wash- 

 ington, and Clarke. It is more than probable that 

 the exceptional fertility of the soils of this region is 

 in great measure due to the presence of these phos- 

 phates. In the upper part of the white limestone 

 (Yicksburg), I have not yet been able to detect any 

 unusual proportion of phosphoric acid. 



In this connection it may be interesting to note 

 that Mr. L. C. Johnson, of the U.S. geological survey, 

 has traced the extension of the Alabama cretaceous 

 phosphate beds into Mississippi, along the line point- 

 ed out by me in one of my notes above referred to. 

 The occurrences in Mississippi are quite similar to- 

 those already described in this state. 



Eugene A. Smith. 



University of Alabama, April 20. 



1 Report on cotton-production in Alabama, p. 52. 



