248 LIFE OF THE PLEISTOCENE 



The Yarmouth stratum No. 4 contained the bones of the following mammals: 



Lepus sylvaticus Mephitis mephitica 



Deposits of Yarmouth age have been observed near West Point and Den- 

 mark, Lee County, Davenport, Iowa, and near Woodville, Payson, and Quincy, 

 Adams County, IUinois. 



II. DISTRIBUTION OF THE YARMOUTH BIOTA 

 1. IOWA 



The Yarmouth is represented near Davenport, Scott County, from which 

 place several good sections have been recorded. Pratt 6 recognized this old soil 

 horizon many years ago and published an excellent section, which is copied 

 below. The interpretations are the writer's, based on the works of Leverett 

 and other geologists. 



1. Recent soil 1 foot 



2. Yellow clay (loess) with Succinea obliqua, S. avara, Helicina occulta. Pupa fal- 



lax, H. striatella, (Illinoian loess) about 20 feet 



3. Bluish-gray clay, with shells of above, mammoth remains at junction of (2) and 



(3). (Kansan loess) 3-5 " 



4. Brown peat with Hypnum aduncum and pieces of coniferous wood (Yarmouth) 1 foot 



5. Ancient soil, dark brown color (Yarmouth soil) 2 feet 



6. Boulder clay (blue clay) Kansan till 18 " 



The section was in a cut made by the C. R. I. & P. R. R. west of Davenport, 

 and is interesting as showing evidence of erosion between 3 and 4, evidently 

 accomplished previous to the deposition of the loess stratum number 3. Web- 

 ster 7 later uses the same section, adding the remains of Coleoptera from the 

 ancient soil number 5. Shimek 8 refers the old soil and peat horizons to the 

 Aftonian and the blue clay to the Nebraskan till, but this disposition cannot 

 be correct, the underlying till sheet being clearly Kansan. 



Leverett 9 has published several sections from Davenport, one of which, 

 along Eighth Street between Myrtle and Vine streets, is shown below. 



lowan loess 30 feet 



Reddish-brown surface of Illinoian till sheet, leached and stained during Sanga- 

 mon Interglacial Stage 2J^-3 feet 



Brown calcareous till, crumbling readily; a characteristic Illinoian till 15 feet 



Ash-colored gummy clay with black streaks, apparently of humus, representing 



the Yarmouth Interglacial Stage 2-3 feet 



8 Proc. Daven. Acad. Sci., I, p. 97, 1876. 



7 Amer. Nat., XXII, pp. 415-416, 1888. 



8 Geol. Iowa, XX, p. 376. 



9 Illinois Glacial Lobe, p. 45; the lowan loess also includes the Illinoian loess in its lower 

 part. 



