PLATE XXVIII. 
Loxonema sicula. 
Page 43. 
Fig. 1. A longitudinal section in chert, of a specimen preserving thirteen volutions, enlarged to two diameters. 
Fig. 2. A fragment showing the last four volutions with a portion of the aperture, natural size. 
Fig. 8. The lower volutions of another specimen, enlarged. 
Loxonema robustem. 
Page 40. 
Fig. 4. A cast 'sf the interior, incomplete at the apex. From the limestone of the Upper Helderberg. 
Loxonema sebatteneatem. 
Page 40. 
Fig. 5. A cast of the interior, nearly entire, from the Schoharie g'rit, Schoharie, N. Y. 
Loxonema Hamilton::.®. 
Page 45. 
Fig. 6. A specimen in limestone preserving thirteen volutions, the last one imperfect. 
Fig. 7. A cast of the interior, in the Goniatite limestone of the Marcellus shale. 
Fig. 7a. An enlargement of the striae on several of the volutions for comparison with other species. 
Loxonema hydraulicum. 
Page 44. 
Fig. 8. An enlargement of a fragment preserving three volutions, showing the constricted suture and char¬ 
acter of the striae. 
Loxonema rectistriatum. 
Page 130. 
Fig. 9. A specimen with the apex imperfect, natural size. 
Fig. 9a. An enlargement of the surface to show more distinctly the character and direction of the striae. 
Loxonema l.®viescelem. 
Page 131. 
Fig. 10. A specimen of the ordinary form of the species. 
Loxonema l.®yiescelem, var. ? 
Fig. 11. An elongated, slender form, preserving about nine volutions, associated with the preceding, and 
without any characteristic markings of the surface. 
Loxonema breviculum. 
Page 132. 
Fig. 12. A longitudinal section of the specimen. 
Loxonema postremem. 
Page 132. 
Fig. 13. An internal cast which preserves marks of the striae upon the last volution. 
