716 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 127 
Types.—Holotype: 117390c ; figured paratypes: 117388c,d, 117390a, 117391; 
unfigured paratypes: 117388a,b, 117390b,d-n. 
Horizon and locality—Oranda formation in Virginia: 0.6 mile northwest of 
Linville Station, Broadway (15’) Quadrangle; on the Bowman Farm, 4 mile 
east of U. S. Highway 11, about 1 mile southwest of Woodstock, Edinburg 
(15’) Quadrangle ; just west of the junction of County Highways 617=910, and 
777 about 4 mile north of Green Mount Church, Broadway (15') Quadrangle. 
In Strasburg (15’) Quadrangle: on U. S. Highway 11, 4 mile south-southwest 
of Tumbling Run, southwest of Strasburg; on Virginia Highway 55, 0.4 mile 
west of U. S. Highway 11, north edge of Strasburg (type section of Oranda 
formation) ; on U. S. Highway 11, 1 to 14 miles southwest of Strasburg; along 
the railroad 4 mile west of Strasburg. 
Discussion—Good specimens of this species are hard to obtain. The shell was 
apparently a fragile one and was easily broken up. It is also an odd fact that the 
brachial valve is exceptionally rare. A single specimen only was obtained. This 
species is characterized by its large size and beautiful ornamentation. In com- 
parison to G. glyptus it has more of the larger costae at the front margin than 
does the Effna form. 
GLYPTAMBONITES ? PLATYS (Butts) 
Sowerbyella platys Butts, Virginia Geol. Surv. Bull. 52, p. 200, 1940; ibid., p. 100, pl. 95, 
fig. 17, 1942. 
This is a small specimen of poor preservation and uncertain generic characters. 
It is a young specimen, besides, whose generic affinities cannot be established 
from exterior examination. It might belong to Palaeostrophomena or possibly 
Glyptambonites, in which it is here provisionally placed. The specimen is actu- 
ally not adequate for a specific diagnosis. It has nothing to do with Sowerbyella 
which has a strongly convex pedicle valve. 
The specimen is 5.9 mm. long and 10.4 mm. wide at the hinge. The sides slope 
obliquely toward the middle, and the front margin is broadly rounded. Cardinal 
extremities acute. Pedicle interarea long, apsacline; interarea of the brachial 
valve short and hypercline. Surface marked by three generations of strong cos- 
tellae in a mat of fine costellae. Pseudodeltidium and chilidium narrowly rounded 
and elongate as in Palaeostrophomena and Glyptambonites. 
Horizon and locality The stratigraphic position of this specimen is not cer- 
tainly known. A label in Butts’ handwriting states “Strasburg No. 7.” This 
suggests that it is bed 7 of Ulrich’s section along the railroad tracks just east of 
Strasburg Junction (or 3 mile west of Strasburg). If this is the correct interpre- 
tation of the label, the specimen came from the Edinburg formation (Cyrtono- 
tella zone). The matrix on the specimen is in accord with this designation. This 
would be bed c of the geologic section in the vicinity of Strasburg. (Bassler, 
1909, p. 56.) 
