DEVONIAN FAUNAS. 
Sy) 
©o 
Or 
STROPHEODONTA sp. undet. 
Plate XLI., Figs. 7-8. 
Associated with the specimens identified as S. magnifica there are 
others representing another species, which are apparently members of 
the genus Stropheodonta, although the crenulated hinge has not been 
observed. They are all imperfectly preserved, and cannot be identified 
with any degree of certainty with any of the described species of the 
genus. The shell is much more strongly coneavo-convex than 8. mag- 
nafica, the convexity of one pedicle valve, 30 mm. in length, amounting 
to 8mm. The radiating markings are also different, the coste being 
sharper and more or less alternating in size. The specimens, especially 
the larger ones, are usually considerably wider than long, one external 
impression of the concave brachial valve being 34 mm. long by 48 mm. 
wide. It is possible that these specimens represent an undescribed 
“species, but the material available for study is too unsatisfactory to 
warrant the establishment of a new species. 
LEPTAENA RHOMBOIDALIS (Wilck.). 
Plate XLI., Fig. 10. 
See, also, pp. 228, 278, 302, 366. 
This is not a common species in the fauna, but the specimens ob- 
served do not essentially differ from those in the earlier Helderbergian 
faunas. 
ANOPLIA NUCLEATA Hall. 
Plate XLI., Fig. 9. 
See, also, p. 349, pl. XLVI. 
Specimens of this species from the “trilobite bed” are not different 
from those in the overlving beds, except in usually being of somewhat 
smaller size. 
