842 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 127 
Horizon and locality.—Edinburg formation (Cyrtonotella zone) in Virginia: 
In the ravine at the switch 4 mile east of Strasburg Junction, Strasburg (15’) 
Quadrangle. 
Edinburg formation (Nidulites zone) in Virginia: Beside the road along 
Tumbling Run, 14 miles southwest of Strasburg; on U. S. Highway If, at 
Hupp Hill, 1 mile north of Strasburg, Strasburg (15’) Quadrangle. 
Edinburg formation (Liberty Hall facies) in Virginia: 14 miles south of 
Wadesville, Winchester (15’) Quadrangle. 
Shippensburg formation (nodular shaly zone below Nidulites) in Pennsyl- 
vania ; 13 miles west of Kauffman, Chambersburg (15’) Quadrangle; in the rail- 
road cut 24 miles southwest of Marion, Chambersburg (15’) Quadrangle. 
Shippensburg formation (Nidulites zone) in Maryland: In a cut on the west 
bank of Conococheague Creek on U. S. Highway 40, 7 miles west of Hagers- 
town, Williamsport (15') Quadrangle. 
Discussion.—This is a rare species, and good specimens are very difficult to 
obtain. In size it is intermediate between C. homostriata and C. grandis, being 
generally larger than the first. Its sides are usually more oblique and the cardi- 
nal extremities more alate than in C. homostriata. Cyphomena homostriata is 
somewhat more finely costellate than the lower Edinburg species and has a flat- 
tened umbo, whereas C. angulata has the umbo narrowly swollen to form a 
short, low fold. 
CYPHOMENA GRANDIS Cooper, new species 
Plate 224, D, figures 23-36 
Shell large for the genus, transversely subrectangular, the hinge forming the 
widest part; sides gently oblique; anterolateral extremities moderately rounded ; 
anterior margin indented; surface marked by 3 to 4 costellae in I mm. at the 
front margin. 
Pedicle valve with lateral profile strongly convex and with the greatest con- 
vexity located anterior to the middle; visceral region convex in lateral profile. 
Anterior convex, strongly domed and with steep sides. Visceral region mod- 
erately convex ; umbo gently convex ; geniculated region narrowly convex; trail 
long, gently convex in lateral profile. Median area of trail occupied by a broad 
and shallow sulcus. Interareas subequal. Muscle area small, subcircular. 
Brachial valve concave, the most concave part located just posterior to the 
place of geniculation. Visceral region nearly flat; umbo nearly flat. 
Measurements in mm.— 
Brachial Hinge Thick- Surface Trail 
Length length Midwidth width ness length length 
TLOLOY POY Persist News. oaversto Te 10.5 18.6 ? 4.3 19.0 II.0 
Paratype (11762Ib)... 13.9 ? 20.0 ? i 22.5 12.0 
af (117620)... to 10.0 L743 ro 4.4 16.5 7.0 
Types.—Holotype: 117621a; figured paratypes: 117620, 117621b; unfigured 
paratype: 11762Ic. . 
Horizon and locality—Martinsburg formation (part with Brongniartella= 
