PLATE 46. 
Athyris yittata. 
Page 
289 
Figs. 1-4. 
1-4. Dorsal, ventral, profile and front views of a specimen from the Falls of the Ohio, pre¬ 
senting the ordinary characters of the species. 
In the description of the internal spires of this species, page 290. the letter h is used to indi¬ 
cate the junction of the intercalated lamellae, but was accidently omitted from the 
figure on page 289. The corrected figure is therefore inserted in this place. 
Athyris Vittate. 
Figs. 5-31. Athyris spiriferoides. . 
5. A small individual without mesial fold or sinus. 
6, 7. Yiews of small specimens, of ordinary form, in which the fold and sinus are partially 
developed. 
8 A larger specimen, showing a strongly lamellose surface. 
9. Dorsal view of a laterally expanded specimen. 
10, 11. Dorsal views of rounded gibbous forms. 
12. Dorsal view of a specimen of the ordinary form and of medium size. 
13. Dorsal view of an extremely broad individual. 
14. Front view of specimen, fig. 13, showing extreme elevation in front. 
15-19. Dorsal, ventral, cardinal, front and profile views of a well defined and moderately 
gibbous form. 
20-24. Dorsal, ventral, cardinal, front and profile views, of a rounded, gibbous and thickened 
shell. 
25. Dorsal view of a large specimen, showing a strongly lamellose surface. 
26, 27. Interiors of a dorsal and a ventral valve, showing hinge structure and muscular im¬ 
pressions. 
28, 29. Dorsal and ventral views of an internal cast of this species, from the Hamilton group, 
Hardy county, Ya., showing very distinctly the impressions of the muscular markings. 
30. Yentral view of a cast from the same formation in Hew York, showing the muscular and 
vascular markings in a still more perfect state. 
31. A specimen, which has been cut to show the spires. The intercalated lamellfe are not seen 
in this view. (See page 284 and plate 47, fig. 8.) 
285 
