PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 233 
Measurements in mm.—Holotype, length 22.0, width 17.0, thickness 6.0 in- 
cluding both valves. 
Type.—Holotype: 109347. 
Horizon and locality—Oranda formation in Virginia: 0.6 mile northwest of 
Linville Station, Broadway (15’) Quadrangle. 
Discussion.—The specimen on which this species is based is somewhat better 
preserved than is usual for the genus. Unfortunately, the usual crushing of the 
beaks has taken place, but the outer shell showing the ornamentation is beauti- 
fully preserved. The species was somewhat more slender than any of those yet 
described in this country. The surface is most like that of L. ? matutinum in 
the strength of the concentric elements but differs in the more closely crowded 
radial rows of granules. 
LINGULASMA MATUTINUM Cooper, new species 
Plate 12, D, figures 9-11 
Species based on fragments of three specimens. Sides subparallel and anterior 
margin broadly rounded. Valves subequal in depth and profiles. Interiors not 
preserved. Ornamentation consisting of fine, even, closely spaced, minutely wavy 
radial lines. Wavy lines with small granules arranged radially. Concentric lines 
closely crowded along the margins and with granules either not present or not 
preserved. Posteriorly radial and concentric elements becoming more or less 
merged to produce the appearance of a minutely beaded surface. 
f 
Measurements in mm.— 
Length Width Thickness 
PAPMSEY PE cates Se ers tra «Vis atc owas ake «tole Mahe 19.6-+ 23.0 11.4 
Baratype /(LOOZA8C) eet osteo ores 25.I-+ 22.4 12.2 
Types.—Holotype: 109348a; figured paratype: 109348c; unfigured paratype: 
109348b. 
Horizon and locality—Upper 25 feet of the Arline formation in Tennessee: 
In glade 4 mile southeast of Friendsville, Concord (T.V.A. 138-SW) Quad- 
rangle. 
Discussion.—This species suggests L. compactum but differs in its much larger 
size and coarser ornamentation. 
LINGULASMA OKLAHOMENSE Cooper, new species 
Plate 12, E, figures 12-17 
Large, very thin shelled; outline subquadrate; longer than wide; lateral mar- 
gins nearly parallel; anterior margin nearly straight ; posterior margin narrowly 
rounded. Anterolateral extremities somewhat narrowly rounded. Valves un- 
equally convex, the brachial valve having the greater depth. Anterior third of 
each valve flattened. 
Ornamentation consisting of radiating lines of low elevations most distinct on 
the median portions and front of the valves but disappearings on the flanks, which 
are marked only by crowded undulations. Elevations consisting of narrow thread- 
