164 Systematic Paleoxtology — Middle Devoxiax 



hook [^lississippian] so that one can look for the ancestors in the 

 Devonian. It is probahlv the most interesting Rrachiopod in the Mary- 

 land collection. Tf you describe it as new, and it seems to be worthy, place 

 it in Productella ( ?)." 



Length, 19 mm. ; width, 20 mm. 



Named in honor of Prof, ("liarles Sclmchert, of Yale University. 



Occurrence. — Pomney' Formation, PTa:miltox Member. Ernstville. 



Collection. — Maryland Geological Survey. 



Family ORTHIDAE 



Genus DALMANELLA Hall and Clarke 



Dalmaxella lexticularis (Vanuxem) 



Plate XIII, Figs. 22-25; Plate XIV, Figs. 11, 12 



Orthis lenticularis Vanuxem, 1842 (non Wahlenberg), Geology New York 



Survey. Third Geol. Dist., p. 139, fig. 4. 

 Dalmanella lenticularis Kindle, 1912, Bull. U. S. Geol. Surv., No. 508, p. 79, 



pi. V, figs. 12-16. 



Description. — Shell snborbicular. subpiano-eonvex. Cardinal angles 

 obtuse or rounded. Greatest width of shell about one-fourth greater than 

 length of hinge-line. Ventiul valve with a subcarinate, gently rounded, 

 median elevation from which the shell slopes regularly to each side. A 

 well developed muscular impression bordered laterally by strong hinge 

 teeth characterizes the interior. The dorsal valve is depressed convex, 

 with a shallow but distinct mesial depression cixtehding the length of the 

 shell. A strongly marked muscular scar extends to the middle of the 

 valve. A broad, low, and sometimes indistinct median ridge divides it 

 longitudinally. Posteriorly it terminates in a bifurcated cardinal process. 

 The entire surface is covered by coarse bifurcating striae, somewhat ir- 

 regular in size, which are grouped in fascicles of four or five. These arc 

 crossed by tine concentric striae. The specimens in this fauna are some- 

 what smaller than those figured by Hall. 



Occurrence. — Eomney Formation, Onoxdaga Mi:.\ihi:r. Wdlianis 

 Poad ;>'^. miles northeast of ('und)erland. 



Collection. — U. S. Xational Museum. 



[E. M. Kindle.] 



