PART I CHAZYAN AND RELATED BRACHIOPODS—COOPER 513 
Finkelnburgia. Actually Polytoechia oakensis is unlike any Little Oak species 
yet seen, and it is more like shells from the underlying Odenville formation. It 
is here suggested that P. oakensis was not derived from the Little Oak, and it is 
therefore not listed with that fauna, 
EREMOTOECHIA Cooper, new genus 
(Greek eremos, solitary; toixos, room) 
Shell fairly large, valves of unequal depth and convexity, the brachial valve 
having the greater depth; hinge narrower than the greatest shell width. Anterior 
commissure uniplicate. Surface finely multicostellate. 
Delthyrium of pedicle valve covered by a convex pseudodeltidium perforated 
by a foramen at its apical end. Interarea moderately long. Delthyrial cavity wide 
and shallow; dental plates short but strong, divergent. Teeth small; crural 
fossettes small. 
Cardinalia suggesting the Canadian genus Tritoechia. Brachial umbo greatly 
swollen ; brachiophores narrow rods supported by shell substance along the sur- 
face facing the brachial valve and the posterior inner wall. Median ridge rudi- 
mentary or obsolete. Cardinal process large, with a short shaft, but large lobate 
myophore. Chilidial plates small. Musculature indistinct. 
Genotype.—Eremotoechia cloudi Cooper, new species. 
Discussion.—Externally this peculiar genus has the appearance of Mimella 
or a small Hebertella in the strongly convex brachial valve, the less convex 
pedicle valve, and the multicostellate ornamentation. However, the presence 
of a pseudodeltidium over the delthyrium, a feature not yet seen in Hebertella 
and its allies, serves to separate Eremotoechia from its homeomorphs. 
The internal features of Eremotoechia are totally unlike those of the Hebertel- 
loids, but indicate relationship with Tritoechia and Pomatotrema of the upper 
part of the Canadian period. The pseudodeltidium of the pedicle valve is per- 
forated by a small foramen. The internal features of the pedicle valve are so 
like those of the Tritoechiidae that this feature, too, probably conformed to the 
family characters. The dental plates of Eremotoechia are shorter and more flar- 
ing than is usual in Tritoechia, but this is probably caused by the lesser length 
of the palintrope. 
The greatest similarity to Tritoechia may be seen in the brachial valve. On 
the exterior, one striking characteristic is preserved in the chilidial plates. Al- 
though these are small and not conspicuous, they are characteristic of the family. 
The beak and umbo of Eremotoechia are more arched and swollen than is usual 
in Tritoechia. For this reason the cardinal process has only a short, curved 
shaft which brings the myophore well beyond the level of the interarea. The 
myophore is strongly lobate, with the central lobe elevated, and the lateral lobes 
depressed. The brachiophores are mostly concealed by callus which spreads over 
the structures of the umbonal chamber. For this reason it is not possible to 
determine the presence or absence of the short and inconspicuous supporting 
plates of the Tritoechiidae. 
