PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 223 
flat and moderately steep. Pedicle groove wide but marked medianly by a low 
longitudinal swelling. 
Brachial valve with beak protruding slightly posterior to the posterior margin ; 
deeper than the pedicle valve with a moderately convex lateral profile ; anterior 
profile broadly convex with moderately steep slopes; anterior slope long and 
gentle. 
Measurements in mm.— 
Length Width Thickness 
Paratype) Geo2o4 iro. Za. I. Bees. 11.2 7.6 1.8 
es CBAGZES a SHAS vhs Tease bas ee 10.3-++ IF 3.0 
3p CRG TGAD NOT: Misites to Soong REN ae 10.8 7h ? 
Types.—Holotype: 116765 ; figured paratypes: 109294, 116763, 116764. 
Horizon and locality—Bromide formation (Pooleville member-Oxoplecia 
gouldi zone) in Oklahoma: At Rock Crossing of Hickory Creek about center 
of sec. 35, T. 5 S., R. 1 E., Criner Hills, Carter County; and on Spring Creek, 
N3 sec. 17, T.2 S., R. 1 W., Murray County. 
Discussion—In ornamentation this species suggests Lingulella virgimiensis, 
but it differs in its more broadly oval form and greater size. 
It is also suggestive of P. sp. 1 from Benbolt formation which has distant 
elevated, concentric lines. The Benbolt species seems to have been a much 
larger shell and with more distantly spaced concentric lines. 
PLECTOGLOSSA sp. 1 
Plate 8,I, figures 19, 20 
This is a fragmentary specimen with imperfect beaks and with the anterior 
third missing. The ornamentation, however, is very distinctive. The valves are 
of subequal depth but with the brachial valve slightly the deeper. The umbonal 
and median regions of this valve are somewhat swollen and have steeper lateral 
slopes than those of the pedicle valve. The ornamentation consists of strong, 
elevated concentric lines, crowded in the posterolateral areas but swinging apart 
and subequally spaced on the median areas. 
Figured specimen.—116774. 
Horizon and locality—Benbolt formation in Virginia: 0.2 mile south of the 
middle fork of Moccasin Creek, 14 miles south of Hansonville, Hansonville 
(T.V.A. 205-SW) Quadrangle. 
PACHYGLOSSA Cooper, new genus 
(Greek pachys, thick; glossa, tongue) 
Elongate elliptical in outline, strongly biconvex but the brachial valve generally 
having the greater convexity. Shell usually thick. Surface marked only by 
growth lines and concentric wrinkles. 
Interior of pedicle valve with posterior structure like that of Lingulella with 
a deep pedicle groove margined by concentrically marked thickenings. Posterior 
margin of brachial valve slightly thickened and without a posterior plate. 
