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Plate XIV 
Endoceras sp. 
Figure 1. A, lateral view; the curvature of the preserved part of the phragmacone has been 
continued laterally so as to indicate the rate of expansion of the conch. B, cross-section at the 
smaller end of the same specimen, showing the size of the siphuncle. (Page 66.) 
Phragmoceras sp. 
Figure 2. A, lateral -view of the living chamber, with the dorsal lobe of the aperture on the right 
and the ventral end of the aperture on the left. The dorsal margin of the aperture is erect, 
as in Phragmoceras, not incurved as in corresponding parts of Gomphoceras. B, the same speci- 
men viewed from above, showing the general appearance of the aperture; if the living chamber 
had been tilted farther forward, the narrow, linear part of the aperture would have reached 
the ventral outline of the figure, and the constricted part of the aperture would have appeared 
narrower. (Page 68.) 
Poterioceras (?) sp. 
Figure 3. A, lateral outline of living chamber, exposing a single segment of the siphuncle at Its 
base; a line of growth is present a short distance below the aperture. B, the same specimen, 
viewed from beneath, showing the dorso-ventral depression of the conch. (Page 69.) 
Rizoceras (? ) sp. 
Figure 4. A, lateral view of living chamber, exposure a single segment of the siphuncle at its base. 
At mid-height there is a conspicuous line of growth. Along the upper left margin of the figure 
there is a projection which may not belong to the shell, and which may be above the margin 
of its aperture. Should it belong to the shell, the specimen could not be a Rizoceroid. B, 
basal view of the same specimen. (Page 70.) 
Orthoceras sp. 
Figure 5. A, dorsal side, showing the shallow dorsal lobes of the sutures of the septa. B, the 
same specimen viewed from above, showing its dorso-ventral depression, and the location 
and small size of the siphuncle. Both figures are magnified 2 diameters. (Page 70.) 
Tjochoceras (? ) sp. 
Figure 6. A, lateral view of the conch, exposing at its smaller end several of the air chambers; 
farther forward, a small part of the shell exposes the transverse surface markings; the remain- 
der of the specimen consists of a cast of the outer surface of the shell, retaining distinct im- 
pressions of the transverse striae, not represented in the figure. B, ventral side of that part 
of the specimen, near its apical end, which retains the transverse surface stria;; this figure 
should be inverted to indicate the location of the hyponomic sinus at former successive stages 
of growth of the conch. C, cross-section of the smaller end of that part of the specimen retain- 
ing its shell, locating the siphuncle. Figure 6A is magnified 3 diameters, figures 6B and C are 
magnified 3 • 5 diameters. (Page 71 .) 
