* 
120 Cincinnati Society of Natural Fitstory. 
middle being only about 0.3 mm. Ventral margin straight or sin- 
nate; ends subequal, the posterior a little the most curved; pos- 
tero and antero-dorsal regions angular, the angles ten or fifteen 
degrees greater than a right angle. Ventral edge slightly thick- 
ened. Marginal or sickle-shaped ridge high, projecting beyond 
the dorsal edge, running parallel with and very close to the abrupt 
posterior margin; then curving more rapidly than does the outline 
of the valve into the ventral margin, it gradually increases its dis- 
tance from the ventral edge, and in a slightly flexuous manner 
traverses the valve for almost its entire length, terminating at a 
point near the middle of the anterior margin. Postero-median 
ridge consisting of three prominently confluent nodes, the upper- 
most projecting considerably beyond the dorsal margin. Antero- 
median node large, prominent and of triangular form. Antero- 
dorsal node projecting prominently beyond the edge, but not as 
high, and only about half as large as the antero-median one. 
Position and locality: Safford’s ‘‘Glade’’ limestone near 
Lavergne, Tenn. ‘These beds may represent the Birdseye of 
New York. 
DEPRANELLA AMPLA, DN. SDP. 
Plate VAT Ty Fig 2: 
Valves subelliptical, comparatively ventricose, 2.5 mm. long by 
1.5 mm.high. Ventral and dorsal margins sub-parailel, the latter 
straight, forming an angle with the posterior margin and rounding 
into the anterior end, which in its turn rounds with a somewhat 
more gentle curve into the gently convex ventral margin. Antero 
and postero-ventral regions equally curved. Dorsal end of the 
sickle-shaped marginal ridge projecting beyond the margin. From 
here it runs nearly parallel with the posterior and ventral margins 
of the valve. Two strong nodes on the dorsal slopes. The 
anterior one is very prominent and pointed, and projects obliquely 
outward and dorsally beyond the edge. ‘The posterior tubercle is 
a little smaller and not so high, but otherwise similar. Between 
them a slight depression. Surface smooth. 
In being rather ventricose this species resembles D. mzfvda, but 
differs in having only two strong nodes where that form has six to 
eight small ones. 
Position and locality: Chazy limestone, bottom of Kentucky 
River gorge, at High Bridge, Ky. 
