102 
Aug. F. Foerste 
along the hinge-line is 4.5 mm. The height of the hinge-area is 
5.3 mm. The radiating striae of the brachial valve are rather 
coarse, one or two finer striae occurring between some of the 
coarser ones. At 25 mm. anterior to the beak, about 10 of the 
coarser striae occur in a width of 5 mm. Radiating striae of 
the pedicel valve distinctly finer and more numerous, about 15 
in a width of 5 mm., at a point 25 mm. from the beak, not count- 
ing the finer intercalated striae. Posterior half of the pedicel 
valve concentrically wrinkled. Hinge-area broadly triangular, 
5.3 mm. in height at the beak. 
Strophomena sulcata, VerneuiP^ 
{Plate I, Figs. ^ A, B, C ; Plate XI, Figs. 2 A, B) 
Strophomena sulcata was described by de Verneuil in the Bulle- 
tin Societe GMogique de France, vol. V, page 350, in 1848. Figs. 
4 a, and 4 h, on plate IV, accompanying the original description, 
suggest the presence of rather coarser radiating striae than those 
typical of the Richmond species usually identified as Strophomena 
sulcata] theReight of the hinge-area of the pedicel valve, as figured, 
is too great, the anterior outline of the shell appears too incurved 
for a specimen exhibiting the hinge-area well, and the lateral 
outlines of the shell are not those most common, although occa- 
sionally found. De Verneuirs collection at present is located at 
the Ecole des Mines, at Paris. Neither Strophomena sulcata nor 
Protar ea verneuili can be found there. The types apparently 
have been lost. However, the reference to the conspicuous sinus 
of the valve at present called the pedicel valve, and the statement 
that Strophomena sulcata is found in the blue limestone of Ohio 
and Indiana, are sufficient to indicate that the Richmond species 
was being described. Strophomena sinuata is so very rare in 
Indiana, that it is extremely unlikely that this species was obtained 
by de Verneuil from that state. Strophomena sulcata, as identi- 
fied from the Richmond, however, is common at several horizons 
in both states, and always attracts the attention of collectors. 
Shells small; width usually varying between 18 and 23 mm., 
rarely equalling 30 mm. Ratio of length to width usually between 
0.67 and 0.75, but it may be as low as 0.61 and as high as 0.80. 
Bulletin, Societe Geologique de France, vol. v, p. 350, 1848. 
