PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 333 
Measurements in mm.— 
Length Width Thickness 
Pedicle s valve: (LIOSA7) sic a. eyes. c wigs ca oli aye 10.5 14.8 2.5 
Brachial valve (rl0s40)). =... wok eect ee ee 9.4 12.5 2.0 
Figured specimen.—116846 ; described specimen: 116847. 
Horizon and locality —Table Head series in Newfoundland: At Table Point; 
south side of Stearing Island, Cow Head, Lower Head. 
Discussion.—This species is suggestive of P. fascicostellata but differs in pro- 
portions, size and details of the ornamentation. 
PLEURORTHIS sp. 2 
Plate 32, C, figures 5, 6 
A fine silicified pedicle valve has the following characters: subquadrate in 
outline ; sides gently rounded, anterior margin broadly rounded. Surface costel- 
late, costellae bifurcating and somewhat bundled near the middle, fairly evenly 
spaced along the anterior margin, about 2 to the millimeter. 
Umbo swollen; sulcus originating at about the middle, broad and shallow but 
producing a short tongue; folds bounding sulcus somewhat narrowly rounded ; 
posterolateral and lateral slopes long and steep. Lateral profile convex with the 
greatest convexity in the umbonal region. Anterior profile with steep sides but 
somewhat sunken median region. 
Interior with wide and deep delthyrial cavity; dental plates short and reced- 
ing ; teeth small but with deep fossettes. Lateral plates along the delthyrial edge 
narrow. Muscle area large but individual scars not visible in the specimen. 
Measurements in mm.—116848, length 11.7, width 14.5+, thickness 5.0. 
Figured specimen.—1 16848. 
Horizon and locality—Lower middle part of the Table Head series in New- 
foundland: North of Table Head. 
Discussion.—This specimen may be conspecific with P. imbecilis, but the un- 
usual preservation does not permit accurate comparison with the usual decorti- 
cated specimens of P. imbecilis. 
Subfamily PropucToRTHINAE Schuchert and Cooper, 1931 
Aberrant and specialized Orthacea characterized by exceedingly short inter- 
areas or none at all and having the exterior form of the productid brachiopod. 
Muscles of the pedicle valve deeply entrenched ; brachial valve with much short- 
ened brachiophores. 
Genus PRODUCTORTHIS Kozlowski, 1927 
Productorthis Koztowskt1, Bibl. Liberae Polonae, fasc. 17 (separate), pp. 1-21, 1927.— 
ScHucHERT and Cooper, Mem. Peabody Mus. Nat. Hist., vol. 4, pt. 1, p. 82, 1032. 
This genus is characterized by its external resemblance to the productids of 
the Carboniferous and Permian. The pedicle valve, like that of “Productus,” is 
usually convex. Some details of the ornament are quite unlike those of “Pro- 
