92 
BULLETIN OF THE LABORATORIES 
Platyceras bivolve, M. and w. ? 
A single specimen is doubtfully identified with this species. 
Quite small, very ventncose, composed of (less than) two closely 
coiled rounded volutions; spire not elevated; inner whorl minute, 
outer whorl very rapidly expanding, ventricose, expanding especially 
downward; section of volution broadly ovate, broadest externally; 
aperture with a faint sinus on the upper and lower external aspects. 
With the last. 
Platycej'as sp. Cf. p. paraliuTYi, M. and w. 
(Plate I, Fig. 23, (Fig. 22?) 
We have a few specimens resembling P. pafaliiim^ which differ 
from the above in having a well-defined revolving ridge and groove of 
the upper surface. The spire is minute and the aperture not very 
oblique. With the above. 
' Dentaliu7)% grafivillp.nsis, sp. n. 
Closely related with grandcEVuni^ Win. 
Shell large, straight, oval in section ; tapering about .078 in one 
inch, marked except near the aperture by fine thread-like stride which 
cross the surface nearly at right angles and are more or less regular. 
Casts are nearly perfectly smo^dh. This species most nearly resem- 
bles D. canna, but is always oval in section. The striae nearly seem 
to cross the shell at right angles and on well-preserved specimens are 
strong and elevated. No evidences of longitudinal markings were 
seen. The length may have exceeded 8 cm. The longest fragment 
measures 49 mm. The longer diameter at the apertural end is 9 mm, 
at the apical 5 mm ; another 50 mm. long measures aperturally 10 
mm, apically 6 mm, or about 8 mm. contraction per cm. D. gran- 
daevum is said to expand more rapidly, but may not prove distinct. 
Free stone at Granville. 
Goniatites lyoni, M. and W. 
Fragments apparently indistinguishable from this species were col- 
