THE LOESS OF NACHEZ MISS. 311 



turbed loess above the talus, and the absence of modern shells 

 of the same species from the immediate vicinity of the par- 

 ticular exposures from which the shells were obtained, leave no 

 doubt that they too are true loess fossils. The single specimen 

 of Pupoides was collected in such talus, but its appearance is 

 that of a loess fossil. Moreover, the species occurs in the loess 

 elsewhere. It is therefore here included as a fossil. 



In some cases the fossil shells were imbedded in larg-e lime- 

 stone nodules, and occasionally small nodules form partial 

 casts of the shells. Some are shown in Plate V. Fossils were 

 collected from twenty-six exposures at Natchez, and from a 

 cut along the Vicksburg and Meridian Railway at Vicksburg, 

 and the several locality sets were kept separate. The accom- 

 panying table of species gives the number of fossils of each 

 species collected from each exposure,* thus giving a compre- 

 hensive view of the distribution and relative abundance of the 

 several species. In making comparisons, however, it must be 

 borne in mind that the several exposures are not of equal ex- 

 tent, nor are they even relatively equally fossiliferous. Eight 

 of the larger exposures! proved to be non-fossiliferous. Ex- 

 posures 1, 2, 3 and 4, are really in the same large cut, and 

 exposures 5 and 6 are likewise opposite sides of one cut, while 

 on the other hand No. 1 1 is a more or less broken series of 

 exposures around the great "gulf," shown on the map, just 

 south of Natchez. It is especially fossiliferous on the south 

 and east sides of the "gulf." 



Numbers 1, 2, 3, 6, 7, 8, 9, n and 17, are the most exten- 

 sive of the fossiliferous exposures, and relatively the richest. 

 They are all located in the southwestern part of the area under 

 discussion. 



Exposures 19 to 26, inclusive, along the Liberty road, are 

 mostly smaller cuts and "guts" along a wagon road, and are 

 not to be compared with the large exposures mentioned. 



*The Natchez exposures are numbered, the number at the top of each 

 column corresponding to the number on the map. No fossils were 

 found in the exposures not included in the table. 



t Compare map and table of fossils. 



