754 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 127 
Measurements in mm.— 
Brachial Surface Mid- Hinge Thick- 
Length length length width width ness Height 
Elolotypertieis. okt. Je 12.8 Tra 14.5 17.4 TOOul) | 22 5.5 
Paratype (117444m) . 13.5 ip 18.0 17.0 18.9 ? 7:3 
s (117443)... 12.7 12.2 17.5 17.9 16.5 ey 5.9 
ee (117444e).. 14.7 i 19.0 17.2 18.0 ? ? 8.0 
Types.—Holotype: 117444d; figured paratypes : 117442a-e, 117443, 117444a-c, 
e-h, 123284; unfigured paratypes: 117444i-m. 
Horizon and locality.—Effna-Rich Valley formations in Virginia: At Porter- 
field Quarry, 5 miles east of Saltville, Maccrady (T.V.A. 218-NW) Quadrangle ; 
McNutt Quarry, 12 miles southwest of Bland, Burkes Garden (15’) Quadrangle. 
Edinburg formation (lower Liberty Hall facies) in Virginia: 1.8 miles S. 
4° W. of Bethel Church, 5.9 miles due east of Harrisonburg, Harrisonburg (15’) 
Quadrangle. 
Botetourt formation in Virginia: 1 mile northwest of Lexington, Lexington 
(15’) Quadrangle. 
Benbolt formation in Virginia: 4 mile southeast of Richpatch, Eagle Rock 
(15’) Quadrangle. 
Pratt Ferry formation in Alabama: 0.2 mile southeast of Pratt Ferry, Blocton 
(15’) Quadrangle. 
Discussion.—This species is one of the largest and most beautiful of this genus. 
It is characterized exteriorly by having strong and distant costellae in a mat of 
fine costellae. The distant nature of the larger costellae is maintained on the 
geniculated trail as well as on the posterior part. In this respect it differs from 
L. tennesseensis, its nearest relative, in which the trail is marked by fairly 
crowded major costellae. 
LEPTELLINA SUBCARINATA Cooper, new species 
Plate 190, E, figures 32-39 
Shell wider than long with rectangular or obtuse cardinal extremities; lateral 
margins gently rounded; anterior margin broadly rounded to somewhat nasute. 
Surface multicostellate, costellae of 3 sizes, many of the ones of intermediate size 
intercalated at the place of geniculation and occupying the front slope which is 
thus marked by many of the larger costellae. About 60 of the strong and inter- 
mediate costellae may be counted at the front margin of an average-size shell. 
Pedicle valve moderately convex with the greatest convexity in the midregion. 
Anterior profile only moderately convex with moderately steep sides sloping 
away from a low, rounded median elevation. Fold low, narrow, extending to 
the front margin. Interarea moderately long with a narrow delthyrium and nar- 
rowly arched pseudodeltidium. 
Brachial valve having a moderate concavity, deepest in the posterior part of 
the median region. Concavity extending forward nearly to the front margin 
in correspondence with the fold of the pedicle valve. Lateral regions bounding 
