PART’ I CHAZYAN AND RELATED BRACHIOPODS—COOPER 999 
a feature that generally differentiates it from Pionodema. Like the latter, Fasci- 
fera also has the swollen, hollow costellae that are a constant feature of the 
Schizophoriidae. These hollow ribs are developed in varying degree among the 
species, some having many, others few. They also complicate the identification 
of species because their development in the same species is not uniform. 
FASCIFERA CONVEXA Cooper, new species 
Plate 268, B, figures 3-6 
Small, subcircular in outline, valves subequally convex, sides and anterior 
margin rounded; hinge narrow. Anterior commissure rectimarginate. Sur- 
face finely costellate, costellae crowded and slender, 4 or 5 to the millimeter at 
the front margin. Scattered swollen costellae also present. 
Pedicle valve gently convex in lateral profile with the front third to half de- 
pressed or geniculated toward the brachial valve; anterior profile somewhat 
narrowly swollen in the median region with slightly convex, long, and fairly steep 
lateral slopes. Umbo subcarinate, the carination dying out near the middle of 
the valve. 
Brachial valve moderately convex in lateral profile, broadly and moderately 
convex in anterior profile. Umbonal and median regions swollen. Sulcus origi- 
nating at the beak, narrow and moderately deep, extending from beak for about 
two-thirds the valve length, becoming lost in the anterior swelling along the 
margin. Flanks moderately swollen, short and steep sided next to the sulcus 
but with long slopes to the margins. 
Brachial interior with characteristic brachiophore plates. 
Measurements in mm.— 
Brachial Hinge 
Length length Width width Thickness 
TAQIOUV PS | Bae ocvec sv outs 8.9 8.6 0.7 6.1 4.8 
Paratype (117303b)..... 0.4 8.8 0.9 7.0 4.5? 
ie CT I94036)) 43 «cic 9.3 8.9 9.4? 6.7 5.0 
Types Holotype: 117303a; figured paratype: 117303c; unfigured paratype: 
117303b. 
Horizon and locality—PBenbolt formation in Tennessee: 1.6 miles northeast 
of Heiskell; on U. S. Highway 25W, 200 feet south of Claxton, both on Powell 
Station (T.V.A. 137-SE) Quadrangle. 
Discussion—This species is characterized by its nearly circular form, the 
fine, even costellae, the fairly strongly convex valves, and the small size. It differs 
from F. subcarinata and F. dalmanelloidea in the ornamentation and circular 
outline. It differs from F. stonensis in the small size and fine costellae. 
FASCIFERA DALMANELLOIDEA Cooper, new species 
Plate 149, A, figures 1-3; plate 153, D, figures 33-47; plate 153,'E, figures 48-53 
Fairly large for the genus, valves subequal in depth, subcircular in outline, 
slightly wider than long; greatest width at the middle; hinge about three-fourths 
