NO. 2 BRACHIOPOD SUPERFAMILY STENOSCISMATACEA GRANT 105 



Holotype.— USNM 124408a, Cooper, 1956a, pi. 61D, figs. 42^7; 

 this paper, pi. 9, fig. 2a. 



Occurrence. — Magdalena Group, Grapevine Canyon, Sacramento 

 Mountains, N.Mex. (details in Cooper, 1956a, p. 525). 



Age. — Pennsylvanian. 



Measurements. — Dimensions of the holotype and four paratypes are 

 given by Cooper (1956a, p. 525). The average length is about 8 mm., 

 width about 9 mm., and thickness about 5 mm. 



Comparisons. — Coledium bozvsheri is characterized by its small size, 

 transverse subpentagonal outline, moderate convexity, weak but dis- 

 tinct costae on the anterior of the fold, smooth flanks, short spon- 

 dylium and short, strongly curved camarophorium. It most nearly 

 resembles C. obesum (Clark) from the Mississippian of Montana, dif- 

 fering in its wider outline, more numerous costae on the fold, and 

 smooth flanks. It is similar in size to C. explanatum (McChesney), 

 but differs in its proportionately wider outline and lower convexity, 

 and especially in its more numerous and weaker costae on the fold, 

 and absent costae on the flanks. It is much smaller than C. erugatum 

 n. sp. which lacks costae, and smaller than C. torvum n. sp. whose 

 costae are very weak and located far anterior. It is not likely to be 

 confused with the greatly different species C. therum (Walcott) and 

 C. crassum (Hamlet) (pi. 18, fig. 6). Both C. undulatum n. sp. and 

 C. evexum n. sp. have costae on the flanks, which differentiate them 

 from C. bowsheri. 



COLEDIUM CESTRIENSIS (Snider) 



Plate 12, figs. 1-ld ; figures 23, 24 



Camarophoria cestriensis SNIDER, L. C, 1915, Okla. Geol. Survey Bull. 24, pt. 

 2, p. 85, pi. 4, figs. 15-16; EASTON, W. H., 1943, Journ. Paleontology, vol. 

 17, No. 2, p. 131. 



Original description (Snider, 1915). — Shell small, subovate to sub- 

 pentagonal, length and width nearly equal, the greatest width anterior 

 to the middle of the shell. The dimensions of the largest shell and one 

 of average size are as follows: length of pedicle valve, 13 mm. and 

 10.5 mm. ; length of brachial valve, 11 mm. and 9 mm. ; greatest width, 

 12.5 mm. and 9.5 mm. ; thickness, 9 mm. and 6.5 mm. 



Pedicle valve arched from beak to front, greatest convexity in the 

 umbonal region, slope steep toward the cardinal margin, and very 

 gentle to the anterolateral margin. The mesial sinus begins posterior 

 to the middle of the valve, and deepens rapidly anteriorly being pro- 

 duced into a lingual extension deeply inflecting the margin of the 

 brachial valve, with a single, ill-defined, rounded plication in the ante- 

 rior portion. Beak small and incurved. The median septum usually 



