APPENDIX. 
31 
fourth of the vertical diameter. The floor of the neural canal is raised to 
the superior margin of the ball. 
The vertebra resembles the fourth in advance of the first bearing 
chevron bone in Lepidosteus. It differs from it generically, solely in the 
completeness of the neural arch above, since it is longitudinally fissured in 
the existing genus. 
PNEUMATOSTEUS NAHUNTICUS. Cope. 
The specific characters of this fossil are as follows : The cup is a ver 
tical oval, slightly truncate below, and openly concave truncate above. 
Its form is not unlike that seen in some of the Pythonomorpha. The 
neural arch is much contracted transversely opposite the neural spine. The 
surface of the bone is very smooth, except a few slight rugae near the rim 
of the cup. 
MEASUREMENTS. 
In. Lin. 
Length of centrum, 1 0 
Width u “ (between lateral septa) 7.1 
Depth of cup, S.T 
Width of cup, 7.9 
Depth of ball, 8.5 
Length of base ?pleurapophysis, 6.8 
“ “ “ nenrapophysis, 7. 
Width neural canal (external, front,) 5.2 
“ “ (internal, behind,) 2.8 
The large cells are exposed by the fractures of portions of the bone. 
The largest are at the posterior base of the haemal arch and at the sides of 
the former 1.5 line in diameter. These measurements indicate a gar of 
six feat in length, if of usual proportions. 
The specimen on which this species is established was found by the 
writer on a pile of Miocene marl on the plantation of Nathan Edgerton 
in Wayne county, North Carolina. Its interstices are filled with a hard 
clay matrix, similar to that which adheres to Cetacean remains in the hard 
stratum in the lower part of the Miocene shell bed of that region. The 
color is black. 
DIODON ANTIQUUS. Leidy , Proc. Acad. Nat. Sciences. 
Superior and inferior jaws from the Miocene. This fish was described 
from transported and much worn specimens from the Ashley river, 
