802 Report or THE State Groxroaist. 
reaching for nearly the entire length of the valve and rising ver- 
tically, beneath the lateral jugal processes, almost to the jugal 
angle. 
Shell substance fibrous, impunctate. 
Type, Anoplotheca venusta, Schnur (sp.). 
Distribution. Middle Devonian (Eifel and Torquay). 
Subgenus Ceelospira, Hall. 1863. 
(Plate 39, figs. 8-17.) 
Shells concavo-convex, oval or circular, with coarse or fine 
radial, simple or compound plications. The pedicle-valve has dis- 
tant teeth arising from the lateral cardinal slopes, and in front of 
the umbonal cavity are a pair of rather deep oval diductor sears, 
which embrace the anterior extremities of two narrow, less exca- 
vated adductors. These are separated by a narrow, more or less 
conspicuously developed median ridge. 
The cardinal process has the same structure as in ANoPLOTHEOA, 
consisting of a central portion curved backward to, or slightly 
beyond the hinge and faintly bilobed on its posterior extremity. 
The crural bases are consolidated with the central process and 
are continuous with the socket walls. There is a stout median 
ridge dividing the muscular impressions and supporting the 
cardinal process. 
The crura are slender and rather long, slightly converging 
toward their apices, forming an acute angle where they meet 
the primary lamellz, the latter turning outward and backward 
and remaining widely separated throughout their extent. The 
coil is lax, the ribbon making but about three voluti ns, and the 
cones, though very slightly elevated, have their apices directed 
outward, toward the lateral slopes of the pedicle-valve. The 
shells vary considerably in convexity both naturally and from 
accidental compression, and where the internal cayity is shallow 
the spirals may appear to be coiled almost in a plane. 
The umbonal curves of the primary lamellz are very broad 
and stout; the jugum arises on their posterior limb, is broad and 
strong, its lateral processes curving gently forward and thence 
upward, being elevated and acutely angulated at the apex. 
Beyond the junction of the lateral processes the jugum is con- 
tinued as a simple stem which is inclined backward and may 
54 
