PART AT CHAZYAN AND RELATED BRACHIOPODS—COOPER 821 
Types.—Holotype: 117669a; figured paratypes: 117664a, 117665, 1176606, 
117667, 117668, 117669b, 117670a-c. 
Horizon and locality—Oranda formation in Virginia: 0.6 mile northwest of 
Linville Station, Broadway (15’) Quadrangle; 4 mile east of Strasburg, Stras- 
burg (15’) Quadrangle; just west of the junction of Virginia Highways 617= 
gio, and 777, + mile north of Green Mount Church, Broadway (15’) Quad- 
rangle. 
Martinsburg formation (part with Brongniartella=Salona) in Virginia: On 
Virginia Highway 617=910, 0.15 mile north of Green Mount Church, $ mile 
northwest of Linville Station, Broadway (15’) Quadrangle. 
Martinsburg formation (Simwites bed) in Pennsylvania: 1 mile south of 
St. Thomas, Mercersburg (15’) Quadrangle; Carlisle, Carlisle (15’) Quad- 
rangle. 
Rodman formation in Pennsylvania: At Bellefonte, Bellefonte (15’) Quad- 
rangle. 
Salona formation in Pennsylvania: At Salona, on Fishing Creek, Lock Haven 
(15’) Quadrangle. 
Rysedorf conglomerate in New York: Near Albany. 
Carters formation in Alabama: 5 feet below the top of the limestone in the 
quarry 0.3 mile north of Gate City, Birmingham Special (15’) Quadrangle. 
Edinburg formation (Cyrtonotella zone just above the siltstone) in Virginia: 
200 yards east of U. S. Highway 11, on Hiatt Run, 3 miles northeast of Win- 
chester, Winchester (15’) Quadrangle. 
Dark shale under Eureka quartzite in Nevada: Under 2 knobs of Eureka 
quartzite, north side canyon, 3.1 miles N. 32° E. of Blair (Segura) Ranch, 
Antelope Mountains, Roberts Mountains (1°) Quadrangle. 
Discussion.—This species is characterized by the discontinuous character of 
the concentric wrinkles, the swollen umbonal region of the pedicle valve, the 
elevated rim around the place of geniculation, the nearly right-angled genicula- 
tion and long trial. This species differs from the L. tenuistriata Sowerby identi- 
fied by Foerste from the Saltillo formation in west Tennessee in having a differ- 
ent outline, the Appalachian shells being more quadrate. The Saltillo shell does 
not have the elevated rim at the place of geniculation nor the swollen umbonal 
region. No other American species of true Leptaena are known to which this 
species may be compared. 
Leptaena ordovicica is a rare species in most localities of the Oranda forma- 
tion. It is locally abundant, however, as at the Linville locality. 
Two specimens from the Cyrtonotella zone near the base of the Edinburg 
formation are referred to this species. These specimens are smaller than is usual 
in the Oranda forms, but the essential specific characters of L. ordovicica are 
present. These are the earliest specimens of true Leptaena yet found in North 
America. 
