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PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 963 
Types.—Holotype: 111794g; figured paratypes: 111794b-d, 117351a,c, 
117352n,0, 117353, 117354a,b; unfigured paratypes: 1117942,e,f,h, 117351b,d-m; 
figured specimen: 117358a. 
Horizon and locality—Chatham Hill formation in Virginia: 1.2 miles S. 31° 
E. of Sharon Springs, Burkes Garden (15’) Quadrangle; Grayson Farm, 4 miles 
southwest of Bland, Bland County. 
Edinburg formation (Cyrtonotella zone) in Virginia: 4 mile west of Stras- 
burg, Strasburg (15’) Quadrangle. 
Botetourt formation (Cybeloides zone) in Virginia: Opposite dam on North 
Fork of Shenandoah River, north side, 1.5 miles N. 61° E. of Edinburg, Edin- 
burg (15’) Quadrangle. 
Discussion.—This species is characterized by small size, strong costellae, and 
circular outline. It also represents a full development of the bizarre characters 
of the cardinal process. The species is one of the earliest known of the dalmanel- 
lid brachiopods on this continent. It differs from C. cristifera in its smaller size 
and more rotund form. 
CRISTIFERINA CRISTIFERA Cooper, new species 
Plate 158, B, figures 6-11; plate 159, C, figures 12, 13; plate 160, B, figures 11-15; 
plate 161, D, figures 37, 38 
Shell large for the genus, subcircular in outline; hinge moderately wide; 
greatest width at about the middle; sides gently rounded; anterior margin 
strongly rounded; anterior commissure gently sulcate. Costellae 2 or 3 to the 
millimeter at the anterior margin. 
Pedicle valve fairly strongly convex in lateral profile; anterior profile strongly 
domed ; umbo narrowly convex, the convexity broadening and finally disappear- 
ing toward the front margin; median region swollen; anterior slope convex, 
long, and steep ; lateral slopes long and steep. Interarea moderately long, curved, 
apsacline. Dental plates short and thick; muscle field small, narrow; vascula 
media moderately developed. 
Brachial valve gently convex in lateral profile; broadly and gently convex in 
anterior profile and with the median region depressed and the lateral slopes short 
and steep. Sulcus narrow and shallow, extending from umbo to anterior margin 
where it is shallowest. Flanks bounding sulcus slightly convex. Brachiophores 
short and thick; notothyrial cavity choked by a greatly thickened cardinal proc- 
ess with enormous median plate which fills the delthyrium. 
Measurements in mm.— 
Brachial Hinge 
Length length Width width Thickness 
Holotypei Gi. Soa, 0.4 8.6 9.3 7.0 5.0 
Paratype (117357a)... 10.6 10.0 10.7 8.0 4.8 
Types.—Holotype: 117356a; figured paratypes: 117355a, 117357b; figured 
specimen: 117358a; unfigured paratype: 1173574. 
Horizon and locality—Oranda formation in Virginia: On the Bowman Farm, 
about I mile southwest of the center of Woodstock and 0.3 mile east of U.S. 
