﻿PART II CHAZYAN AND RELATED BRACHIOPODS — COOPER 1 173 



Plate 170 

 isophragma 



Page 



A. Isophragma ricevillense Cooper, new species 737 



(1) Plasticine replica of the pedicle exterior, X 2, paratype, iiOQ23g; (2) brachial 

 view of a complete specimen preserving its shell, X 1, holotype, 110918a; (3-7) 

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

 holotype; (8) impression of the pedicle interior showing the scalloped thicken- 

 ings inside the anterior margin, X 2, paratype, 110923b; (9) plasticine replica 

 of the pedicle interior prepared from the preceding, X 2, and showing the ante- 

 rior thickenings; (10) impression of the interior of another pedicle valve, X 2, 

 paratype, 110923a; (11) plasticine replica of the pedicle interior, X 3, prepared 

 from the preceding mold; (12) impression of the brachial interior, showing the 

 long duplex ridge, X 2, paratype, 110923c; (13) plasticine replica of the brachial 

 interior, X 2, prepared from the preceding; (14) impression of another brachial 

 interior, X 2, paratype, 110923d; (15) plasticine replica of the brachial interior 

 prepared from the preceding mold, X 3, showing the double median ridge, 

 cardinal process, and pallial marks. 



Athens formation (base), just east of the intersection, 2.\ miles south-south- 

 east of Riceville, Calhoun (T.V.A. 125-SW) Quadrangle, Tenn. 



B. Isophragma sulcatum Cooper, new species 739 



(16) Brachial view of a poorly preserved specimen, X 2, holotype, 110917. 



Just above Lenoir formation with Maclurites and under the Pratt Ferry, 

 0.15 mile southeast of Pratt Ferry, Blocton (15') Quadrangle, Ala. 



C. Isophragma extensum Cooper, new species 735 



(17) Brachial view of a complete specimen, X 2, paratype, 117375. 



Little Oak formation, junction Bailey Gap and main roads, Cahaba Valley, 

 SW^S W| sec. 13, T. 19 S., R. 2 W., i| miles northeast of Newhope Church, 

 Vandiver (15') Quadrangle, Ala. 



D. Isophragma extensum Cooper, new species 735 



(18) Brachial view of a young specimen, X 2, paratype, H7376f 5(19-22) respec- 

 tively anterior, pedicle, brachial, and side views of a complete, well-formed 

 specimen, X 2, holotype, 117376a; (23) posterior of the preceding, X 3, showing 

 cardinal process, chilidium, and pseudodeltidium ; (24) brachial view of the pre- 

 ceding, X 3, showing ornamentation in detail ; (25) brachial view of a young 

 and mucronate specimen, X 3, paratype, 117376c; (26) interior of an old pedicle 

 valve, X 2, showing extreme thickening of the interior, paratype, 117376-I; (27) 

 pedicle interior of a young specimen, showing anterior, subperipheral ridges, 

 X 3, paratype, 1 17376c ; (28) another pedicle interior of a young specimen, X 3, 

 paratype, 117376k; (29) brachial interior, X 4, showing duplex ridge, thick- 

 shafted cardinal process, and brachiophores, paratype, U7376d. 



Arline formation, 100 yards southwest of the Negro Cemetery, \ mile north- 

 east of Friendsville, Concord (T.V.A. 138-SW) Quadrangle, Tenn. 



Plate 171 

 Glyptambonites, Isophragma 



A. Isophragma extensum Cooper, new species 735 



(1) Brachial view of a young but complete specimen, X 3, paratype, ii09iid; 

 (13) brachial interior, X 3, showing elevated ridge, paratype, 110911a. 



Arline formation, 1,500 feet south of the mouth of Burnett Creek, Shooks 

 Gap (T.V.A. 147-NE) Quadrangle, Tenn. 



(2) Brachial exterior of an imperfect specimen preserving both valves, X 2, para- 



