353 
[Foerste. 
PLATE VI. 
Fig. i. Strophomena Hanoverensis, ¥ oerste. Ventral valve and a line 
indicating its convexity. H. I. 
Fig. 2. Strophomena patenta, Hall? Apparently a sickly form, dorsal 
valve, and a line indicating its convexity. H. I. 
Fig. 3. Belleroplion ( Bucania ) exigua, Foerste. Fig. 3, side view ; 3 a, 
lines indicating the character of a section transverse to fig. 3. H. I. 
Figs. 4, 5. Orthis calligramma, Dalman var. flabellites. Fig. 4, cast of 
a ventral valve; fig. 5, cast of a dorsal valve. H. I. 
Fig. 6. Lf-ptcena transversalis, var. elegantula, Hall. Ventral valve, and 
a line indicating its convexity. H. I. 
Fig. 7. Cyrtolites Youngi, Foerste. Fig. 7a, a magnified side view with 
a line indicating the real size of the specimen ; fig. 7, lines showing the 
outlines of a section vertical to fig. 7a, also magnified. H. I. 
Fig. 8. Atrypa marginalis, var. multistriata , Foerste. Ventral valve. 
H. I. 
Fig. 9. Atrypa marginalis, Dalman. Fig. 9, ventral valve; fig. 9a, a 
dorsal valve. B. O. 
Figs. 10-11. Cornulites clistans, Hall. Fig. 10 resembles a species of 
Tentaculites ; fig. 11, both in the cast and in the exterior views, is a figure 
of a true Cornulites. C. T. 
Fig. 12. Bhynchonella neglecta, Hall. Ventral valve. H. I. 
Fig. 13. Bhynchonella acinus , var. convexa, Foerste. Fig. 13a, dorsal 
valve; fig. 136, ventral valve ; fig. 13c, side-view. H. I. 
Fig. 14. Bhynchonella acinus , Hall, from the Niagara of Waldron, In- 
diana, the most distinct form; fig. 14a, dorsal valve; fig. 146, ventral 
valve ; fig. 14c, side view. 
Figs. 15-16. Leptcena obscura, Hall? Fig. 15, dorsal valve, and a line 
indicating its convexity ; fig. 16, ventral valve and a line indicating its con- 
vexity. C. T. 
Fig. 17. Holopea obsoleta, var. elevata, Foerste. C. T. 
Figs. 18-19. Leptoccelia? hemispherica, Sowerby. Fig. 18, ventral valve, 
with a line indicating its convexity; fig. 19, dorsal valve, with a line in- 
dicating its convexity. C. T. 
Figs. 20-21. Phacops pulchellus, Foerste. Fig. 20, a glabella; fig. 21, 
a pygidium. C. T. 
Fig. 22. A glabella of Cyphaspis Clintoni, Foerste. C. T. 
Figs. 23-24. Bhynchonella decemplicnta, Sowerby? Fig. 23, a dorsal 
valve and a side view of the same ; fig. 24, perhaps a young form of this 
species. C. T. 
Fig. 25. Strophomena corrugata, Conrad. The elongated form figured 
first by Hall under this species, but not the typical form of Conrad. C. T. 
Figs. 26-27. Strophomena corrugata, var. phtri- striata, Foerste. More 
like that figured second by Hall under S. corrugata. It is not impossible 
that this may prove to be the typical form of Conrad. Fig. 26, dorsal 
PROCEEDINGS B. S. N. H. VOL. XXIV 23 JANUARY, 1890. 
