PLATE LXXYIII. 
ObtHOCERAS OBLIQUUM, 0. VASTATOR, n. sp.* 
Page 243. 
Fig . 1. A fragment, retaining a large portion of the chamber of habitation, and about twenty adjacent 
chambers. (Ventral view?) 
Fig. 2. A septum from figure 1 showing the position of the siphuncle, and the areola surrounding its inser¬ 
tion in the septum. 
Fig. 3. Lateral view of another fragment presenting the extreme, but apparently normal, obliquity of the 
septa. 
Fig. 4. A small septate portion of an individual referred to this species. The specimen is flattened in a 
dorso-ventral direction, destroying the curvature of the septal margins over the dorsal and 
, ventral sides. 
ORTHOCERAS LTJXTTM. 
Page 244. 
See Plates 35, 76, 77, 78 B, 81, 112. 
Fig. 5. A fragment of this species considerably compressed. This figure represents a common condition of 
the specimens. Schoharie, JSf. Y. 
Fig. 6. A septum of the preceding specimen, showing the areola surrounding the siphuncle, and extending 
to the ventral side. 
Fig. 7. Longitudinal section of a distorted fragment, preserving some traces of the siphuncle. Clarks¬ 
ville, jst y. 
* The name 0. ohliquvm having been preoccupied by Eichwald in 1860, the name of this species is here 
changed to 0. vastator. See corrections and Addenda. 
