﻿1 196 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I27 



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 complete specimen, X 2, paratype, 117540a; (10) brachial view, X 1, of the pre- 

 ceding; (17) pedicle interior, X 3, showing the pallial marks, paratype, 117540b; 

 (18) brachial interior, X 3, showing cardinalia, paratype, H7540d; (21, 22) 

 brachial and pedicle views of a small specimen showing variation in ornamenta- 

 tion, X 2, paratype, 117540c. 



Bromide formation (Mountain Lake member), Spring Creek, sec. 17, T. 2 S., 

 R. 1 W., Murray County, Okla. 

 B. Sowerbyella social is Cooper, new species 794 



(23) Brachial view of a complete specimen, X 1, holotype, 117525a; (24-27) re- 

 spectively brachial, posterior, anterior, and side views, X 2, of the preceding 

 specimen; (28) well-preserved specimen showing brachial view, X t, paratype, 

 98207b; (29, 30) same as preceding, X 2, brachial and pedicle views; (43) 

 brachial interior, X 3, showing cardinalia and thickened anterior, paraytpe, 

 117525b; (31-35) respectively pedicle, brachial, side, anterior, and posterior 

 views of a complete specimen, X 2, paratype, 117523a; (41) pedicle interior, 

 X 3, showing muscles and pallial marks, paratype, 117527a; (44) brachial inte- 

 rior, X 3, showing cardinalia, paratype, 117527c. 



Wardell formation, Lloyd Carter's barn, 0.8 mile by road northeast of the 

 school at Rye Cove, Clinchport (T.V.A. 188-NW) Quadrangle, Va. 



(36, 38) Brachial and anterior views of a complete specimen, X 2, paratype, 

 117530b; (37, 39) side and brachial views of a specimen with more rectangular 

 outline, X 2, paratype, 117530a. 



Wardell formation (Sowerbyella bed), Evans Ferry section, 0.8 mile north 

 of Indian Creek, on U. S. Highway 25E, Howard Quarter (T.V.A. 162-NW) 

 Quadrangle, Tenn. 



(40) Interior of the pedicle valve, X 2, showing exceptional development of the 

 pallial markings, paratype, 1 17522. 



Wardell part of Dryden formation, north side of Lone Mountain Creek, just 

 west of the road to Straight Creek, 0.8 mile west of Lone Mountain Station, 

 Tazewell (T.V.A. 154-NE) Quadrangle, Tenn. 



(42) Pedicle interior, X 3, showing muscle scars and pallial marks extending 

 anteriorly from the diductor ends, paratype, 117524a. 



Wardell formation, 1 mile north-northeast of Rye Cove, Clinchport (T.V.A. 

 188-NW) Quadrangle, Va. 



Plate 199 

 Sowerbyella 



A. Sowerbyella monilifera Cooper, new species 785 



(1) Brachial view of a complete specimen, X 1, paratype, 117499a; (2-6) respec- 

 tively anterior, posterior, brachial, side, and pedicle views, X 2, of the same 

 specimen; (7) brachial interior showing cardinalia and septa, X 2, paratype, 

 117499b; (8) ornamentation of the brachial valve, X 5, holotype. 



Decorah formation (upper Ion member), cut on Highway 10, |- mile west of 

 Ellsworth, Lancaster (30') Quadrangle, Wis. 



B. Sowerbyella aequicostcllata Cooper, new species 774 



(9, 12) Respectively X 1 and X 2 enlargements of a complete specimen, holotype, 

 H7477f ; (11) side view, X 2, of the preceding specimen; (10) anterior view of 

 a complete specimen, X2 paratype, H7477g; (13, 14) pedicle views, X 2, of 

 two paratypes, 117477b, 117477a; (16) impression of the pedicle interior showing 

 muscle scars, X 2, paratype, 117477c; (17) brachial interior, X 3, showing 

 cardinalia, muscle area, and subdued septa, paratype, H7477d. 



