PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 445 
just northwest of Chickamauga Creek, Kensington (T.V.A. 106-SE) Quad- 
rangle. 
Discussion.—This species has the outline and profile of Campylorthis and thus 
suggests C. lebanonensis. It differs in being a much larger shell with stronger 
ornamentation and somewhat less deep brachial valve. 
CHAULISTOMELLA sp. 1 
Plate 63, A, figures 1-7 
The figured specimens are young because a brachial valve in the collection 
is nearly twice the size of the complete specimen. The species is characterized 
by its subquadrate form, the length and width being about equal. The sides are 
subparallel ; the costellae are closely crowded with about 12 in 5 mm. in the young 
complete specimen but 10 in 5 mm. at the front of the large brachial valve. The 
pedicle valve is unusually convex for the genus, but that may be an indication of 
the youth of the specimen. The brachial valve is strongly convex. The species 
resembles C. mundula in outline but is a much more robust form with a more 
convex pedicle valve. The immature complete specimen measures in mm.: 
Length of pedicle valve 16.4, brachial length 16.5, width at middle 19.4, thick- 
ness 7.9. 
Figured specimens.—117990Aa,b. 
Horizon and locality——Carters formation (O-xoplecia bed) in Alabama: 
Quarry 0.3 mile north of Gate City, Leeds (15’) Quadrangle. 
CHAULISTOMELLA (?) sp. 2 
Plate 126, G, figures 36-40 
Under this designation is placed a small lot of shells that may have other ge- 
neric affinities. They are described because they occur in the Oranda formation 
and may represent the end of a dinorthid line if correctly assigned. Proper ge- 
neric definition will not be possible until the pedicle interior as well as the brachial 
interior is known. 
Small for the genus, subrectangular with the width greater than the length. 
Sides rounded ; anterior margin broadly rounded; hinge narrower than the mid- 
width. Exterior finely costellate and with the striae between the costellae occu- 
pied by prominent concentric fila. 
Pedicle valve moderately concave in lateral profile; broadly concave in anterior 
profile. Umbo narrowly convex, the convexity continued anteriorly as a low 
fold. Flanks bounding fold gently concave. Interarea long and strongly apsacline. 
Brachial valve gently convex in lateral profile and with the maximum con- 
vexity in the posterior half; anterior profile bilobed; sulcus originating at the 
umbo, widening and deepening to the anterior margin where it occupies about 
one-third the width. Flanks bounding sulcus somewhat narrowly convex; pos- 
terolateral slopes short and steep; posterolateral extremities flattened. Cardinal 
process slender ; notothyrial platform moderately thickened. Sockets deep, brachi- 
ophores short and blunt. 
