XXX 
LIST OF WOODCUTS. 
Page 
Fig. 27. Huronia (diagrammatic) 199 
28. obliqua (structural) 200 
29. Actinoceras Clouei (structural) 200 
30. Huronia vertebralis 203 
31. Actinoceras (simctural) 205 
32. Sactoceras docens 208 
33. Gompboceras (structural) 211 
34. (structural) 212 
35. Tetrameroceras (outline of ajgerture) 235 
36. vet as (outline of aperture) 240 
37. Conradi (outline of aperture) 241 
38. Hexameroceras (outline of aperture) 242 
39. Hesoceras Eobemicnm 244 
40. (a) Trimeroceras, (h) Pentameroceras, (c) Septamero- 
ceras (outlines of aperture) 245 
41. Ascoceras Bohemicnm 247 
42. (structural) 247 
43. Yemenili 251 
44. Glossoceras gracile, var. curta 254 
45. a-c. Poterioceras constrictum ; d, e, Poterioceras fusi- 
forme 257 
46. Cyrtoceras depressum 263 
47. obliqnum 269 
48. (Heloceras) clathratnm 304 
49. Gonioceras anceps 325 
50. JoTellania Murrajn 329 
51. Ascoceras 335 
