﻿PART II CHAZYAN AND RELATED BRACHIOPODS — COOPER 1055 



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 Oranda formation along the railroad \ mile west of Strasburg, Strasburg 

 (15') Quadrangle, Va. 

 (6, 7) Pedicle exterior, X 2 and X I, holotype, 116876a. 



Edinburg limestone (Cyrtonotella zone), along the railroad about i mile east 

 of Strasburg Junction, Va. 



C. Orthambonites acutiplicatus ( Raymond) 294 



(8) Somewhat exfoliated brachial exterior, X 2, paratype, Carnegie Mus. 5460; 

 (9) small pedicle valve, X 1, lectotype, Carnegie Mus. 5458; (10, 11) respec- 

 tively X 2 and X 1 enlargements of a large pedicle valve, paratype, Carnegie 

 Mus. 5459. 



Chazy group (Day Point ? formation), Valcour Island, Lake Champlain, 

 Plattsburg (15') Quadrangle, N. Y. 



D. Orthambonites pancicostatus (Ulrich and Cooper) 3 10 



(12, 14) Respectively X2 and Xi enlargements of a pedicle valve, hypotype, 



109834m; (13, 15, 16) side, pedicle, and brachial views of an imperfect speci- 

 men, X 2, hypotype, 109834a; (19) pedicle view, X 1, of the preceding; (17, 18) 

 brachial valve, X 2 and X 1, hypotype, 109834b. 



Upper Pogonip group (lower part of Rhysostrophia bed), Ikes Canyon, east 

 side Toquima Range, Roberts Mountains (i°) Quadrangle, Nev. 



E. Orthambonites dinorthoides Cooper, new species 3 01 



(20) Brachial interior, X 2, paratype, 109822a ; (22) imperfect pedicle valve, X I, 

 paratype, 109822b. 



Upper Oil Creek formation, West Spring Creek, 3 miles east of Pooleville, 

 Murray County, Okla. 



(21) Exterior of a small brachial valve, X I, paratype, 109823d; (24) nearly per- 

 fect pedicle valve, X I, holotype, 109823b; (25) nearly perfect brachial interior, 

 X 2, paratype, 109823a; (26) pedicle interior, X 2, paratype, 109823c. 



Oil Creek formation (614 feet above base), west side U. S. Highway 77, 

 NEiNEi sec. 25, T. 2 S., R. 1 E., Carter County, Okla. 

 (23) Large brachial valve, X 1, paratype, 109821a; (27) impression of the pedicle 

 interior showing the muscle scars, X 2, paratype, I0982id. 



Oil Creek formation, sec. 14, T. 2 S., R. 1 E., about 5 miles north-northwest of 

 Springer, in Murray County, Okla. 



Plate 34 

 Orthambonites 



A. Orthambonites bifurcatus Cooper, new species 297 



(1) Exterior of a silicified pedicle valve showing the ornamentation well, X 2, 

 paratype, 116869; (2-4) side, brachial, and pedicle views, X 2, of a nearly com- 

 plete specimen, the holotype, 109798c; (6) holotype, X 1; (5) brachial view of 

 another small individual, X I, paratype, I09798g. 



Upper Pogonip group {Rhysostrophia zone), north side of Ikes Canyon 1 mile 

 above the entrance, east side of Toquima Range, Roberts Mountains, (i°) 

 Quadrangle, Nev. 



B. Orthambonites occidentalis Cooper, new species 308 



(7-9) Pedicle, side, and brachial views, X 1, of the holotype, 109807a. 

 Horizon and locality same as preceding. 



C. Orthambonites rectangulatus Cooper, new species 310 



(10) Pedicle view, X I, of the holotype, 116877; (11-15) respectively posterior, 

 anterior, pedicle, side, and brachial views, X 2, of the holotype. 



Shippensburg formation (Pinesburg member — just above Echinosphaerites 



