PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 607 
Figured hypotypes.—117168a-c ; 111324. 
Horizon and locality—Lower Martinsburg formation (part with Brongniar- 
tella= Salona) in Virginia: On Virginia County Highway 617=910, 0.15 miles 
north of Green Mount Church, Broadway (15’) Quadrangle. 
Discussion.—The foregoing description is based on five specimens from the 
base of the Martinsburg (Salona) shale at Green Mount Church north of Har- 
risonburg, Va. This is a rare shell in Virginia, and the characters of the speci- 
mens at hand are not in complete conformity with those of the specimens referred 
to this species from New York and elsewhere. 
The National Museum collection of Parastrophina hemiplicata is small and 
unsatisfactory, but even so, it shows clearly that considerable revision is needed 
in this genus. The specimens from Watertown, N. Y., a locality mentioned in 
Hall’s original description of the species, are fairly small shells having a length 
of 11 or 12 mm. and a width of 12 to 15 mm. The Virginia shells are somewhat 
smaller and somewhat rounder than those from Watertown. The latter speci- 
mens are quite different from large ones from Salona, Pa., and Larrabee 
Point, Vt., which have a width of 19 mm. Other specimens from Montreal, 
Quebec, are not unlike the Watertown shells but have different ribbing charac- 
ters. The National Collection specimens, unfortunately, do not have detailed 
stratigraphic information, but the variety of forms indicates beyond doubt that 
they represent numerous levels and that geographic variation also plays a role 
of importance. The species is in need of revision, but this cannot be done with- 
out very extensive collections. The identification of the Virginia specimens is 
thus a tentative one. 
PARASTROPHINA ROTUNDIFORMIS (Willard) 
Plate 117, A, figures 1, 2 
Anastrophia (?) hemiplicata var. rotunda WINCHELL and ScHuUCHERT, Minnesota Geol. 
Surv., vol. 3, pt. 1, p. 383, pl. 30, figs. 32-35, 1895. 
Parastrophia hemiplicata rotunda (Winchell and Schuchert) BAsster, U. S. Nat. Mus. Bull. 
92, vol. 2, p. 945, IQI5. 
P. rotundiformis WitLarp, Bull. Mus. Comp. Zool., Harvard Coll., vol. 68, No. 6, p. 290, 
1928 (not the Virginia specimens). 
The shells from McNutt Quarry, near Sharon Springs, Va., and probably 
those from Thomas Farm, 3 miles east of Blacksburg, Va., from the Effna 
formation undoubtedly belong to Perimecocoelia and should not be identified with 
the Minnesota species which comes from the Trenton (Prosser) formation. 
The specimen figured is exceptional for the fine development of the interior 
details. 
Figured specimen.—87600. 
Horizon and locality—Prosser formation (Prasopora bed), in Iowa: 14 miles 
north of Waukon, Allamakee County. 
