PLATE XXVII. 
Euomphalus (Pleuronotus) Decewi. 
Pages 55 and 137. 
Fig-. 1. A lateral view into the spiral depression, exhibiting the angular form of the aperture, as shown 
where the shell lies upon its base. , 
Fig. 2. The umbilical side of the specimen, stowing the subquadrate form of the aperture as seen from 
beneath. The shell becomes thickened and lamellose towards the mouth. The surface- 
markings rare only partially preserved on a part of the outer volution—the remaining portion 
of the shell having been covered by a Stromatopora. 
Fig-. 3. The upper side of the shell, showing the depressed spire. The surface-markings are in part pre¬ 
served, while much of the anterior portion of the last volution is covered by a Bryozoan. The 
peripheral band is distinctly marked, even where the shell is removed, and the depth of the 
marginal sinus is shown by the direction of the striae—the aperture being filled with Stroma- 
,, [toppra., 
Fig. 4. A section across the centre, as illustrated on plate 15 ; the upper part of the figure, a, cutting the 
yolutio,n, (of a cast) pear the aperture ; b showing the form at half a volution preceding; and c, 
the form at a single ;volution from the aperture. 
Euomphalus (Straparolltjs) clymenioides. 
Page 62. 
Fig. 5. The upper side of a large specimen, preserving a little more than one volution entire, with the 
remaining portion crushed and- ’imperfect; : 
Fig. 6. A smaller specimen, showing a single volution with partial impressions of the remaining volutions. 
Both tire specimens are casts of the interior. 
Euomphalus (Straparollus) Hecale var. corpulens. 
See page 59. 
Fig. 7. The umbilical side of a specimen associated: with OrtMs Tioga, from the Chemung group. 
Euomphalus Tioga. 
Page 56. 
Fig. 8. The umbilical side of a specimen, associated with authentic Chemung fossils at Nichols, Tioga 
county, N. Y. 
