R. ELLSWORTH CALL AND IOWA GEOLOGY 
37 
Call barely escaped making one of the great geological discoveries of the 
century — the establishment of the multiplicity of the Glacial Epoch. 
The Des Moines sections furnished all the evidence but they were not 
properly interpreted. 
Call afterwards extensively studied the loess ' of the upper Mississippi 
Valleys and came to the conclusion that this remarkable loam formation 
was a great lake deposit, accumulated something after the manner of the 
beds of the alleged vast Tertiary lakes of the Great plains region. Here 
again his judgment was at fault, for all of the deposits of this description 
were finally proved to be mainly epirotic formations laid down by the 
winds. His dose association with government folk in the far west 
evidently firmly implanted in his mind this early but erroneous notion. 
His views on this subject are elaborated in a series of articles which 
appear in the American Naturalist. These papers were long worthy 
of careful perusal if for no other reason than that they supplied the 
best summary of our scant knowledge on the loess up to the date of 
their publication. 
During several summers Professor Call served as assistant geologist 
on the Arkansas Geological Survey under Dr. J. C. Branner. His main 
work was on the Crowley Ridge, a long narrow elevation of Tertiary 
formations rising out of the wide Mississippi flood plain in the eastern 
part of the state. The report was published as a special volume of the 
Survey series. 
When resident of Iowa, Call became interested in the artesian waters 
and collected data from a number of deep drill wells put down in 
various parts of the state. His principal results appeared from time to 
time in the Bulletin of the Iowa Weather Service. Many brief papers 
and articles were published on geological subjects in the scientific 
journals. 
Call published most extensively on the mollusks, fishes, and reptiles. 
A synopsis of the Unionidse of the United States formed the initial 
number of a Bulletin series of the Des Moines Academy of Sciences and 
found wide circulation. The Unionidae of Arkansas formed a profusely 
illustrated memoir that was published by the St. Louis Academy of 
Science. His shortep papers on Conchology were many and varied. 
The '‘Anatomy of Campeloma'’' was a model of its kind, and was based 
entirely upon materials obtained around Des Moines. 
One group of mollusks in which Call became very much interested 
was the little known family of the Strepomatid^, turreted snails inhabit- 
ing southern rivers. The Coosa, Black Warrior, and Tombigbee rivers 
of Alabama in particular harbored these water snails. For a number of 
years he was accustomed to collect extensively in these streams and -their 
numerous tributaries. Isaac Lea, Thomas Conrad, Thomas Say and 
Constantine Rafinesque described many species but these were never very 
well defined; and a large synonomy resulted. It was our Iowa natural- 
isfs special mission tol pass in review all the described forms, to collect 
abundantly from all the original localities, and to adjudicate the numerous 
varieties in accordance with modern canons of taxonomy. This he was 
able to do in most satisfactory fashion. Having accomplished this gigantic 
task he generously sent typical and authenticated sets of the shells to 
