PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 859 
Horizon and locality.—“Ottosee” (=Benbolt?) formation in Virginia: On 
U. S. Highway 19, 25 miles west of Paint Lick, Tazewell (15’) Quadrangle. 
BELLIMURINA sp. 2 
Plate 222, F, figure 10 
This is a fairly well preserved brachial interior showing the cardinalia, two 
adductor ridges, and a short median ridge. The specimen is thought to be from 
the Wardell formation, and its locality is 2 miles west of Rye Cove, Clinchport 
(T.V.A. 188-NW) Quadrangle, Virginia. 
Figured specimen.—Columbia Univ. 25873. 
Family CHRISTIANIIDAE A. Williams, 1953 
Smooth or finely costellate Strophomenacea having 4 prominent septa in the 
brachial valve. 
Genus CHRISTIANIA Hall and Clarke, 1892 
Christiania Hatt and Crarke, Pal. New York, vol. 8, pt. 1, p. 208, 1802. 
Shells subquadrate to longitudinally subrectangular with the hinge wider or 
narrower than the width at the middle; pedicle valve strongly convex; brachial 
valve more or less deeply concave. Surface marked by fine concentric lines, 
rarely by fine costellae, and fine growth undulations. 
Pedicle valve: Interarea longer than the brachial one, curved; delthyrium 
more or less closed by an elevated, convex pseudodeltidium; foramen small, lo- 
cated at the beak and cutting the beak and the extreme apex of the pseudo- 
deltidium as in the true Strophomenoidea. 
Teeth moderately small, wide, and short and with small fossettes. Dental plates 
nearly obsolete, usually visible as stout ridges under the teeth. Diductor im- 
pressions linguate, confined to the delthyrial cavity which is very deep because 
of the strongly swollen umbo. Adjustor scars small, somewhat triangular and 
situated just under the dental plates. Adductor scars small and located at the 
posterior of the muscle field just in front of the foramen. Diductor impressions 
surrounding the adductors anteriorly and separated from one another by a more 
or less well defined median ridge. Major pallial trunks extending from the an- 
terior end of the diductor scars directly anteriorly. About a third the length 
from the anterior margin these trunks branching and sending secondary trunks 
in an anteromedian direction. Further branching into tertiary and quaternary 
sinuses taking place near the anterior margin. 
Brachial valve: Brachial interarea twisted into a hypercline position and much 
shorter than that of the pedicle valve. Chilidium strongly convex and well cover- 
ing the posterior and brachial face of the cardinal process. Brachiophores widely 
divergent, moderately long, having the form of a flattened rod with an acute free 
extremity ; brachiophores supported by shell substance deposited on their inner 
faces. Sockets wide and shallow, partially formed by the sloping outer face of 
