PLATE VII 
Fig. 1. Strophomena wisconsinensis. A, pedicel valve; B, brachial valve; 
C, interior of pedicel valve. Wilmington, Illinois. Richmond group. Schuchert 
collection. See also plate IX, Figs. 5 A, B, C. 
Fig. 2. Strophomena vicina. Pedicel valve, magnified 1.5 times. Northeast of 
Becknerville, Kentucky. Paris member. See also this Bulletin, vol. XIV, 
plate VII, Fig. 12 A. 
Fig. 3. Strophomena acuta. A, brachial valve. See also plate IX, Figs. 13 A, 
B. B, pedicel valve; C, pedicel valve; D, brachial valve. A, B, from Schuchert 
collection. C, D, from University of Minnesota collection. Spring Valley, Minne- 
sota. Richmond group. 
Fig. 4. Strophomena planodorsata. A, pedicel valve; B, brachial valve. Man- 
nie clay, forming upper part of Richmond group, a cjuarter of a mile northeast of 
Fly, beyond the home of R. S. Elam. See also plate IX, Figs. 14 A, B. 
Fig. 5. Strophomena neglecta. Interior of pedicel valve. Richmond group. 
Savannah, Illinois. Schuchert collection. See also plate X, Fig. 10. 
Fig. 6. Strophomena planodorsata. Interior of pedicel valve. Richmond group. 
Wilmington, Illinois. Schuchert collection. See also plate IX, Fig. 7. 
Fig. 7. Stropho7nena planodorsata. A, interior of pedicel valve; B, brachial 
valve. See also plate IX, Figs. 8 A, R for other views of 7 B; and Fig. 9 for other 
view of 7 A. 
Fig. 8. Strophomena planodorsata. Interior of pedicel valve, enlarged 2.5 times. 
Richmond group. Iron Ridge, Wisconsin. University of Minnesota collection. 
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