t 
Or 
DEVONIAN FAUNAS. Ro 
CYRTINA VARIA Clarke. 
Plate XLVIII., Figs. 13-16. 
1900. Cyrtina varia Clarke, Mem. N. Y. State Mus. Nat. Hist., vol. 
III., No. 3, p. 49, pl. 6, figs. 15-22. 
Description.—Shell obliquely subpyramidal, its greatest width along 
the hinge-line; cardinal extremities angular, at times somewhat mu- 
cronate. Pedicle valve greatly elevated at the beak, sloping away to 
the lateral and front margins, with a well-defined, narrow mesial sinus 
extending from the beak to the front margin; beak pointed, a little 
incurved ; cardinal area about twice as wide as high, flat or a little con- 
cave toward the beak; delthyrium narrowly triangular, closed below 
by the deltidial plates, the elongated foramen occupying the upper 
portion just beneath the beak. Interiorly the dental lamelle unite at 
their bases and are continued as a mesial septum, which extends nearly 
to the anterior margin of the shell. Brachial valve depressed-convex, 
flattened towards the cardinal extremities; mesial fold low, rounded 
or shghtly flattened, with a faint, median, depressed line. Surface 
of each valve marked by from six to nine simple, rounded or sub- 
angular plications on each side of the fold and sinus and by fine, 
imbricating, concentric, lamellose lines of growth. 
The dimensions of a nearly-perfect specimen are: length of brachial 
valve, 10 mm.; width of same, 17 mm.; height of cardinal area of 
pedicle valve, 7 mm. 
METAPLASIA PYXIDATA (Hall). 
Plate XLVIIL., Fig. 6. 
1859. Spirifer pyxidatus Hall, Pal. N. Y., vol. III., p. 428, pl. 100, 
figs. 9-12. 
Description—Shell semi-elliptical to subtriangular in outline; 
hinge-line about equal to the greatest width; cardinal extremities 
angular or a little rounded. Pedicle valve gibbous on the umbo and 
strongly elevated medially to the anterior margin, flattened toward 
