PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 267 
SCHIZAMBON IRREGULARE Cooper, new species 
Plate 14, C, figures 20, 21 
This species is represented by a single brachial valve that may be distinguished 
from all other members of this genus by the irregularity of its surface markings. 
It is subcircular in outline, moderately convex in profile with the strongest curva- 
ture at the middle. The lateral profile is moderately convex with maximum 
convexity at the middle; anterior profile gently and broadly convex. The umbo 
is smooth; the umbonal region is traversed by a shallow but wide sulcus which 
disappears at about the posterior third. The posterior half of the valve is with- 
out imbrications but is marked by discontinuous short and wavy lines and scat- 
tered spines. The spines are about 1.5 mm. in length. 
Measurements in mm.—Holotype, length 12.0, width 12.0. 
Type.—Holotype: 109669. 
Horizon and locality—Arline formation in Tennessee: On Sevierville Pike, 
3 miles southeast of Knoxville, Knoxville (T.V.A. 147-NW) Quadrangle. 
SCHIZAMBON LINEATUM Cooper, new species 
Plate 14, D, figures 22, 23 
A single brachial valve has unusual characters that separate it from all other 
known species of the genus. The convexity in lateral profile is moderately strong 
and the outline is oval, the shell narrowing posteriorly. In anterior profile the 
valve is broadly convex. The median portion is somewhat swollen and the de- 
scent to the margins is short but moderately steep. The ornamentation consists 
of strong lamellae as is usual for the genus, but the lamellae are ornamented by 
elevated, wavy concentric lines, often as many as 3 or 4 lines to a lamella. Large 
spines occur scattered over the surface, but fine nodes on the concentric lines 
indicate that rows of fine spines covered the entire shell. At the front margin 
the fine spines have a length of 2 mm. 
Measurements in mm.—Holotype, length 16.0, width 14.5, thickness 3.5. 
Type.—Holotype: 109671. 
Horizon and locality—Wardell formation in Virginia: I mile northeast of 
Rye Cove, Clinchport (T.V.A. 188-NW) Quadrangle. 
SCHIZAMBON MACROTHYRIS Cooper, new species 
Plate 15, A, figures 1-4; plate 22, L, figures 22-24 
Shell large for the genus, elongate, oval in outline; posterior pointed, lateral 
margins gently rounded, anterior margin broadly rounded. Greatest width at 
about anterior third. 
Pedicle valve gently convex in the umbonal region, very faintly convex in the 
anterior two-thirds. Track of foramen equal in length to one-third the length 
of the valve, widening rapidly. Foramen elliptical. Region about the pedicle 
track ornamented by nearly equally distant, elevated concentric lines which are 
crossed by fine discontinuous radial lines occupying the entire umbonal region. 
