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PALEOZOIC PALEONTOLOGY. 
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STROPHONELLA LEVENWORTHANA (Hall). 
Plate XXXIV., Figs. 1-3. 
1859. Stropheodonta levenworthana Hall, Pal. N. Y., vol. III., p. 
189, pl. 21, figs. 5-7, pl. 23, figs. 1-2. 
Description.—Shell longitudinally semi-elliptical, length greater 
than the breadth, hinge-line crenulated, equaling the greatest width 
of the shell. Pedicle valve depressed-convex on the umbo, flattened 
toward the cardinal margin, abruptly inflected toward the lateral and 
front margins, giving to the entire valve a deep concavity; beak in- 
conspicuous, cardinal area linear. Brachial valve shghtly concave in 
the umbonal region, strongly convex or geniculate toward the front 
and lateral margins, following somewhat closely the curvature of the 
opposite valve. Surface of both valves marked by fine, irregularly- 
bifurcating, raised, radiating strize, which are crossed on the flattened 
portion of the valves by more or less irregular, concentric wrinkles. 
The dimensions of a large specimen are: length, 36 mm.; width, 
43 mm.; convexity of brachial valve, 15 mm. 
Remarks.—This is one of the rarer species of the New Scotland . 
fauna in New Jersey, and has been observed only in the lower cherty 
limestone member of the formation, where it is always in a poor con- 
dition of preservation. In some respects the species resembles Leptena 
rhomboidalis, but, when compared with that species, it is resupinate, 
the pedicle, and not the brachial, valve being the strongly-concaye one. 
This character, with the crenulated hinge-line, which can only rarely 
be detected in the New Jersey specimens, will always distinguish the 
two species. The species also somewhat resembles Stropheodonta beckei 
in its markings, but in that species the pedicle valve is depressed-con- 
vex and not deeply concave, as in the shell under discussion. 
LEPTAENA KHOMBOIDALIS (Wilck.). 
Plate XXXIII., Fig. 10. 
See, also, pp. 228, 278, 328, 366. 
The New Scotland and Becraft representatives of this species do not 
materially differ from those in the Coeymans limestone fauna, al- 
though they frequently attain a somewhat greater size. 
