PLATE LYL 
Gyroceras transversum. 
Page 384. 
Fig. 1. Lateral view of a large fragment, showing the curvature and enlargement of the tube, 'and the 
rows of rounded nodes over the chambered portion. The strong test is shown covering the 
dorsal side of the tube. The arching, transverse striae, represented on the chamber of habita¬ 
tion, do not exist on the specimen. Goniatite limestone of the Marcellus shale. Near Man¬ 
lius , N. Y. 
Fig. 2. Ventral view of the preceding, showing the sinus in the margin of the aperture, the crenulated 
zone at the base of the grand chamber, and the profile of the nodes on the sides of the tube. 
Fig. B. Ventral view of a smaller septate fragment, showing the variation in the depth of the air-chambers 
toward the apex, and a longitudinal, flattened band along the ventrum. Goniatite limestone. 
Near Manlius, N. Y. 
Fig. 4. A septum of the preceding, showing the size and position of the siphuncle on the convex ventral 
side of the tube. 
Nautilus liratus, var. juvenis. 
Page 411. 
Fig. 5. The dorsal side of the specimen, preserving the grand chamber and several imperfect air-chambers, 
showing the broad elliptical aperture, and the slender, carinate revolving striae, with fine trans¬ 
verse striae. The position of the siphuncle cannot be satisfactorily determined, and is not 
represented. Hamilton shales. Cazenovia, IV Y. 
Fig. 6. The ventral side of the same specimen, showing the revolving striae much subdued, while the trans¬ 
verse striae are essentially the same as on the opposite side. The specimen is free from 
weathering or wearing, and the surface-markings are in their natural condition. 
