130 
Aug, F. Foerste 
beds at Cincinnati^ Ohio. As a matter of fact, they have a con- 
siderable vertical range^ and form what might be called a museum 
species, where forms are at times discriminated that can not be 
kept distinct in the field. Strophomena suhtenta presents similar 
difficulties. 
Plectorthis fissicosta, Hall 
{Plate VIII, Fig. 4) 
A figure of the pedicel valve of the type specimen, preserved in 
the American Museum of Natural History, is added to those of 
the brachial valve of the same specimen published on plate IV, 
in voL XIV of this Bulletin. This valve is crushed centrally, 
but the features are not obscured. 
Austinella scovillei^ Miller 
(Plate VIII, Figs. 8 A, B, C) 
In the original description of this species, it is stated that the 
types were collected near Lebanon, Ohio. As a matter of fact, 
however, they were found about 7 miles northeast of Lebanon, 
at a locality then known as Freeport, but now called Oregonia. 
Here they occur 5 feet below the upper Hebertella insculpta 
horizon, in the upper part of the Blanchester division of the 
Waynesville member of the Richmond. The present location 
of the types figured by Miller is unknown, but the species is 
readily identified, and a number of specimens from the James 
collection, preserved in the Walker Museum, at Chicago Uni- 
versity, are here figured. Some of these are labelled as coming 
from Oregonia, others as having been found at Blanchester, evi- 
dently at the same horizon. The exposures at Lebanon belong 
to the Fort Ancient division of the Wa 3 mesville. 
Austinella scovillei is regarded as the genotype of the pro- 
posed group, Austinella. Figs. 8 B, and C, on plate VUI of this 
Bulletin, illustrate the narrow, rectangular muscular area of the 
pedicel valve, characteristic of this group. From the antero- 
lateral angles of this area, branching vascular ridges diverge, 
only indistinctly indicated in the accompanying figures. 
Journal, Cincinnati Soc. Nat. Hist., voL V, p. 40, 1882. 
