322 NATURAL HISTORY BULLETIN. 



The first of the quoted statements shows clearly that Dr. 

 A. Binney's information concerning the limits of loess, evi- 

 dently obtained at second-hand, was very much confused. 

 The description of the deposit, probably furnished to Dr. Bin- 

 ney by Mr. John Bartlett who collected the shells, shows that 

 there was here an indiscriminate reference of practically all 

 the looser superficial deposits to the loess, probably including 

 even tertiary.* 



Evidently only the uppermost "yellowish calcareous loam" 

 is loess, and even a portion of this may be brown loam. From 

 this part of the deposit "a few fluviatile species" are reported, 

 together with many terrestrial shells. None of these "fluvia- 

 tile shells" are mentioned by name. Not only is there doubt 

 as to the exact character of the deposit from which they came, 

 but Dr. Binney's use of the term "fluviatile" was not exact. 

 This is shown in a discussion of the Wabash deposit, probably 

 loess, written at about the same time as the paper on the Nat- 

 chez loess, or a little earlier,f in which he says that it "con- 

 tains, in vast numbers, terrestrial and fluviatile shells," and in 

 a foot-note on the same page he enumerates the land shells 

 (ten species), and adds that these occur "together with several 

 species of Limnea, Planorbis, Amnicola, Valvata." As these 

 are the only aquatic shells mentioned he evidently considered 

 them fluviatile. Limncea and P 7a nor bis are pulmonate pond- 

 snails which occur commonly in small ponds. Valvata, while 

 sometimes found in larger streams and lakes, often occurs in 

 small ponds, and the same is true of Amnicohi, though the 

 shell here referred to may be Pomatiopsis lapidaria, a terres- 

 trial species, which was then included in Amnicola. The 

 aquatic shells here mentioned indicate, both by their scarcity 

 and their habits, that the bodies of water in which they oc- 

 curred were individually and collectively of slight extent. 



*See Wailes, 1. c, pp. 269 et seq. , for discussion of the deposits in 

 which the marine forms mentioned by Binney occur. 



tTerr. Air-breathing Moll, of the U. S. , vol. I, p. 181, written by Dr. 

 Binney prior to 1847, the year of his death, but published under the 

 editorship of A. A. Gould in 1851. 



