PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 659 
Oligorhynchia is at present known only from the Southern Appalachians in 
the United States. It is also present, if interpretation of Cowper-Reed’s figures 
is correct, in the Balclatchie and Stinchar limestones of the Girvan District, Scot- 
land. The specimens described by Cowper-Reed as Camarella ? conybearet seem 
to belong to this genus, at least from their external appearance. No details of 
the interior are given in the description, but figure 23 on plate 22 (Reed 1917) 
shows short dental plates not unlike those seen in Oligorhynchia in the 
Appalachians. 
OLIGORHYNCHIA ANGULATA Cooper 
Plate 125, C, figures 37-46; plate 125, D, figures 47-49; plate 126, C, figures 10-12; 
plate 127, B, figures 9-13 
Oligorhynchia angulata Cooper, Amer. Journ. Sci., ser. 5, vol. 29, p. 52, pl. 1, figs. 6, 7, 9-11, 
1935. 
Types.—Lectotype: Y.P.M. S2258; figured hypotypes: U.S.N.M. 117195a-c, 
117196, 118017; paratype: Y.P.M. S2259. 
Horizon and locality—tLincolnshire formation (Hogskin member) in Ten- 
nessee: At Luttrell, Luttrell (T.V.A. 155-NW) Quadrangle, and Washburn, 
Dutch Valley (T.V.A. 154-SE) Quadrangle; on the road to Washburn, 3, 4, 
and 44 miles west-southwest of Thorn Hill, Avondale (T.V.A. 162-SW) Quad- 
rangle; # mile southwest of Mount Eager Church, Hogskin Valley, Powder 
Springs (T.V.A. 154-SW) Quadrangle; 4 mile southwest of Fleanor Mill and 
200 yards north of the highway, Powell Station (T.V.A. 137-SE) Quadrangle. 
Sevier formation in Tennessee: + mile north of Gooseneck, southwest corner 
Louisville (T.V.A. 138-SE) Quadrangle; slope on the west side of the church 
in Guthrie Gap, 2 miles south-southeast of Whitehorn, Bulls Gap (T.V.A. 
17I-SE) Quadrangle; 1.3 miles south of the center of Athens, Athens (T.V.A. 
125-NE) Quadrangle. 
Ward Cove formation in Virginia: On Wallen Creek, east of Virginia High- 
way 70 at Glass’s store, 54 miles southeast of Jonesville, Ben Hur (T.V.A. 
170-NE) Quadrangle. 
OLIGORHYNCHIA BIFURCATA Cooper, new species 
Plate 126, D, figures 13-24; plate 127, A, figures 1-8 
Oligorhynchia sp. Butts, Virginia Geol. Surv. Bull. 52, pl. 87, figs. 18, 19, 1942. 
Shell small, elongate triangular in outline, compressed in both profiles; beak 
erect and sharply pointed ; surface strongly costate. 
Pedicle valve with deep sulcus extending from beak to anterior margin and 
occupied by a single costa located in the front third of the sulcus. Sulcus bounded 
by strong angular, elevated costae with 2 low costae on each side. 
Brachial valve faintly sulcate at the umbo but with a widening sulcus anteriorly 
which is occupied by a single strong costa bifurcated at its front end to accom- 
modate the small costa of the pedicle sulcus. Flanks of costae bounding sulcus 
with a low costa. 
