260 LIFE OF THE PLEISTOCENE 



Succinea verrilli M Helicodiscus lineatus ( = parallelus) 



Pyramidula shimekii Helicina occulta 



" cronkhitei anlhonyi Carychmm exiguum 



In a cut near Hartington, Cedar County, the Wisconsin drift rests upon a 

 calcareous marl, which contains a few fresh water shells, six species being 

 recorded. 



Vaii ala tricarinata Galba palustris? 



Planorbis panus Succinea oialis {—obliqua) 



Galba obrussa {=desidiosa) Sphaerium striatinum 



Todd 51 refers this deposit to the late Tertiary, probably the Equus beds of 

 Cope. Similar beds are reported two or three miles east of Harrington. The 

 most probable correlation of these beds would seem to be with the Yarmouth 

 interval. Augheys' 52 list of loess fossils from Nebraska is so unreliable and 

 the identifications are plainly so erroneous that it cannot be used and must be 

 completely ignored. 



3. SOUTH DAKOTA 



The Kansan ice sheet spread over the eastern half of South Dakota and 

 upon its surface the remains of Yarmouth life have been observed. In Clark 

 County Todd 53 observed the following section, six miles from Bradley, in 

 section 35, Spring Valley Township: 



1. Black loam 3 feet 



2. Crumbly yellow clay (Wisconsin) 14 " 



3. White marl, containing shells 3 " 



4. Muck, containing wood and shells 9 " 



5. Blue clay (evidently Kansan) 6 " 



Height of section 35 feet 



The white marl contained: 



Vahata tricarinata Planorbis bicat hiatus { — anlrosus) 



Galba humilis modicella, " parvus 



The muck contained shells similar to those of number 3, and also coni- 

 ferous wood and two bivalve mollusks, A nodonta species and Sphaerium sul- 

 catum (= simile). This was evidently a shallowing pond, which was finally 

 filled with loess. 



60 This is an evident misidentification, derrilli being an eastern species, originally de- 

 scribed from Anticosti Island, Gulf of St. Lawrence. Shimek says that it should be stricken 

 from loess lists. 



51 Bull. 158, U. S. Geol. Surv., p. 73. 



62 Hayden's U. S. Geol. Surv. Col. & Adj; Terr., pp. 266-269. 



53 Proc. Iowa Acad. Sci., VI, p. 127. 



