NO. 2 BRACHIOPOD SUPERFAMILY STENOSCISMATACEA — GRANT IOI 



Table 17. — Measurements of Coledium erugatum from the Moore field Formation 



of Oklahoma 



Measurements, in millimeters 



142124 c.18.0 c.18.0 10.0 



such a way that it is possible that they also protruded slightly to form 

 a narrow stolidium. The smooth shell distinguishes this species from 

 C. explanatum (McChesney) and C. cestriensis (Snider). The high 

 narrow fold also distinguishes it from the latter species. Its smaller 

 size and high, narrow fold distinguish it from C. dutroi n. sp., another 

 smooth or nearly smooth species of Coledium. 



The smooth shell of C. erugatum recalls species of Psilocamara 

 Cooper, but there is little resemblance other than smoothness. The fold 

 of C. erugatum is rounded, without the Gothic-arched crest of Psilo- 

 camara, C. erugatum attains much greater size, has a stolidium on the 

 fold of many specimens, and the valves overlap in the posterior ; in- 

 ternally, it has an intercamarophorial plate, a shallower camaropho- 

 rium, and internal structures are proportionately longer. 



Occurrence and abundance. — Upper part of Moorefield Formation, 

 %. mile north of southeast corner, sec. 20, T-l 5-N, R-20-E, Hulbert 

 Quadrangle, Okla (14 specimens USNM 142128) ; Moorefield For- 

 mation, 0.2 mile south of Glendale School, center of east line, sec. 20, 

 T-15-N, R-20-E, Muskogee County, Okla. (7 specimens USNM 

 142126) ; Moorefield Formation, NW>4 SW^ sec. 21, T-15-N, 

 R-20-E, 0.1 mile south of Glendale School, Muskogee Quadrangle, 

 Okla. (3 specimens USNM 142129) ; upper part of Moorefield, 

 NW*4 NW}4 sec. 18, T-l 5-N, R-21-E, 1 mile south of Fort Gib- 

 son, Okla. (2 specimens USNM 142130) ; Moorefield Formation, y A 

 mile south of Glendale School, SE}4 NE*4 sec. 20, T-l 5-N, R-20-E, 

 on road 1 mile east of Oklahoma Highway 10, south of Bayou Manard, 

 Muskogee Quadrangle, Okla. (2 specimens USNM 142131) ; Moore- 

 field Formation, NW/ 4 sec. 18, T-l 5-N, R-21-E, 1% miles south 



