936 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 127 
STROPHOMENA FASCICULATA Cooper, new species 
Plate 256, B, figures 6, 7 
Shell small, attaining a length of about 0.6 inch; subquadrate in outline ; hinge 
straight, not equal to the greatest shell width which is at about the middle; sides 
gently rounded ; anterior margin broadly rounded ; costellae consisting of 2 sizes, 
a large and prominent set marking off fascicles of finer ones; 15 costellae in 
5 mm. at the anterior margin, including 3 of the larger costellae. 
Pedicle valve gently convex in lateral profile and with the maximum con- 
vexity in the posterior half; anterior half somewhat flattened; anterior profile 
nearly flat to very gently convex; umbonal region narrowly convex, the con- 
vexity continued anteriorly as a low fold beyond the middle; region just posterior 
to the middle gently swollen; flanks sloping gently from median region to the 
margins. Pseudodeltidium large, subcarinate. 
Brachial valve gently convex with the maximum convexity somewhat anterior 
to the middle; posterior somewhat flattened; anterior profile broadly and gently 
convex; umbo marked by a shallow sulcus that extends to about the middle to 
merge with the slightly swollen anterior two-thirds; flanks with gentle lateral 
slopes. 
Measurements in mm.— 
Brachial Hinge 
Length length Midwidth width Thickness 
Holotype Ve nde liiteds se eies bas 14.8 13.0 13.3 14.0 ? 
Paratype (117754b).......... 10.4 9.6 13.1 10.2 2.2 
Types.—Holotype: 117754a; figured paratype: 117754b; unfigured paratypes: 
117754c-f. 
Horizon and locality—Peery formation in Tennessee: 7 miles southwest of 
Clinton, Clinton (T.V.A. 137-SW) Quadrangle. 
Discussion.—This species is strongly costellate, and the costellae are strongly 
fasciculated. It suggests Pionomena but differs from P. neumani in having a 
less convex brachial valve, not so strong a development of the umbonal and 
median sulcus, and stronger costellae. It is one of the most strongly fasciculate 
species of Strophomena. 
STROPHOMENA FILITEXTA (Hall) 
Leptaena filitexta Hat, Pal. New York, vol. 1, p. 111, pl. 31B, fig. 3, 1847. 
Strophomena filitexta (Hall) Fenton, Amer. Midland Nat., vol. 11, No. 9, pp. 500-503, pl. 38, 
figs. I-5, 1920. 
Fenton restudied the types of this species which has been widely misidentified 
in Middle Ordovician rocks. He indicates that the only species similar to S. fili- 
texta are S. auburnensis and S. plattinensis, but they are distinct. He also states 
that the cotypes belong to the “typical black Trenton limestone.” The specimen 
(pl. 38, fig. 1) which Fenton says is most clearly depicted by the original descrip- 
tion is a large one having the width about 14 times greater than the length. The 
writer has seen none like this in the collections of Middle Ordovician fossils 
