PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 887 
Types.—Holotype: 123281a; figured paratypes: 123281e,f,j; unfigured para- 
types : 123281b-d,g-i,k-m. 
Horizon and locality—Oranda formation in Virginia: 0.6 mile northwest of 
Linville Station, Broadway (15’) Quadrangle. 
Discussion —This is a very small and delicate species and is the only repre- 
sentative of the genus so far found in the Oranda formation. It is characterized 
by its small size and the delicate character of its cardinalia. It differs from 
R. trentonensis in its smaller size, planoconvex profile, and delicate cardinalia. 
RAFINESQUINA PRESTONENSIS Salmon 
Rafinesquina prestonensis SALMON, Journ. Paleont., vol. 16, No. 5, p. 578, pl. 85, figs. 28-33, 
1942.—Witson, Geol. Surv. Canada, Bull. 8, p. 75, text fig. 4, No. 5; pl. 7, figs. 4a-c, 1946. 
Type.—Holotype: Columbia Univ. 25888. 
Horizon and locality—Rockland formation and Guttenberg member of the 
Decorah formation in Illinois: At Milbrig. 
RAFINESQUINA SINCLAIRI Salmon 
Plate 266, B, figures 5-7; plate 266, C, figures 8, 9 
Rafinesquina elongata SALMON (not Teichert, 1937), Journ. Paleont., vol. 16, No. 5, p. 576, 
pl. 85, figs. 14-17, 1942. 
R. sinclairi SaLtmon, idem, vol. 17, No. 3, p. 309, 1943. 
This name is used for specimens occurring in the Guttenberg member in Wis- 
consin, the probable Guttenberg in Missouri, and the Auburn chert in Missouri. 
The specimens indicate a species variable in length-width relationship and in 
convexity. Both of these features apparently depend on age. The name sinclairi 
is used in preference to R. alternata, to which this shell is related, because the 
ornamentation and cardinal extremities are more like that of the Guttenberg 
species. Rafinesquina sinclairi appears to be somewhat more convex than R. alter- 
nata, and the ornamentation is featured by a preponderance of closely spaced 
strong costellae separated by 1 to 4 of the fine costellae. 
Figured hypotypes.—117858a,b, 117859. 
Horizon and locality—Auburn chert in Missouri: 4 mile east of Auburn, 
Elsberry (15’) Quadrangle. 
Barnhart formation in Missouri: On U. S. Highway 61, 0.1 mile south of Salt 
River, north of New London, Ralls County; on U. S. Highway 61, 0.2 mile 
south of Koch School, NE. corner SWiSW3$ sec. 6, T. 41 N., R. 6 E., 2 miles 
south of Barnhart, Kimmswick (15’) Quadrangle. 
Guttenberg member in Wisconsin: Above the 8 inches of blue clay of the 
Platteville, on Wisconsin Highway 151, 0.7 mile northeast of Dickeyville, Grant 
County ; NW sec. 19, T. 3 N., R. 1 W. Grant County; 2 miles west of Platte- 
ville ; 0.1 mile south of the Little Platte River on Wisconsin Highway 81, 2 miles 
northwest of Platteville, Mineral Point (30’) Quadrangle. 
