Williams.] FAUNA OF ZONE D, ARISAIG, NOVA SCOTIA. 
41 
The following list shows the character of the fauna of the group D: 
1. Lituites. 
2. Phragmoceras. 
3. Ormoceras? 
4. ? long, tapering, and recurved. 
5. Orthoceraa nummulare Sow. 
6. Orthoceras, very like O. bullatumSow. 
7. Orthoceras ibex Sow. 
8. Orthoceras exornatum Dawson. 
9. Orthoceras punctostriatum Hall. 
10. Orthoceras, 4 sp. 
11. Bellerophon trilobatus Sow. 
12. Bellerophon carinatns Sow. 
13. Bellerophon striatus D'Orb. 
14. Bellerophon expansns Sow. 
15. Theca Forbesii Sharpe. 
16. Coleoprion ? sp. 
17. Murchisonia Arisaigensis Hall. 
18. Murchisonia aoiculata Hall. 
19. Pleurotomaria. 
20. Modiolopsis ? rhomboidea Hall. 
21. Modiolopsis subnasuta Hall. 
22. Clidophorus cuneatus Hall. 
23. Clidophorus concentricus Hall. 
24. Clidophorus erectus Hall. 
2">. Clidophorus elongatus Hall. 
26. Clidophorus semiradiatus Hall. 
27. Clidophorus nuculiformis Hall. 
28. Clidophorus subovatus Hall. 
29. Avicula Honey mani Hall. 
30. Pterinea retroflexa. 
31. Orthonota (like many Ludlow spe- 
cies) Salter. 
32. Goniophora cymbseformis Sow. 
33. Chonetea Nova-Scotica Hall. 
34. Chonetea tenuiatriata Hall. 
35. Ortiiis, 2 sp. 
36. Spirifer subsulcatua Hall. 
37. Rhynchonella, 3 sp. 
38. Discina rugata Sow. 
39. Discina ? lineata. 
40. Discina ? tenuilamellata Hall. 
41. Crania Acadiensis Hall. 
42. Lingula sp. 
43. Ilonudonotus Dawsoni Hall. 
44. Homalonotua Knightii Konig. 
45. Dalmania Logani Hall. 
4(f. Phacopa Downingige Salt. 
47. Calymene, different from Blumen- 
bachii Brong. 
48. Proetus Stokesii ? 
49. Beyrichia pustulosa Hall. 
50. Beyrichia equilatera Hall. 
51. Beyrichia, 2 sp. 
52. Leperditia sinuata Hall. 
53. Crinoidea. 
54. Tentaculites. 
55. Cornulites serpularius. 
56. Serpulites n. sp. (in clusters on shell 
of Orthoceras) . 
57. Stenopora. 
58. Heliopora fragilis var. Acadiensis 
Hall. 
The species in this list followed by the name of Hall were all 
described by James Hall l from this locality. 
Mr. Salter examined this fauna, and "unhesitatingly referred it to 
the Ludlow tilestone." This is the upper member of the Silurian of 
modern classification, and is called the Downtonian. 
Dr. Ami has recently made a study of this section, and identified 
the fossils in the Canadian survey office coming from the Arisaig sec- 
tion. His identifications are published in the Proceedings and Trans- 
actions of the Nova Scotian Institute of Science, Halifax, 2d series, 
Vol. I, Pt. I, pp. 185-192. A list of 163 species is given, but the asso- 
ciation of these species into separate faunas is not made in the list, and 
they include both Upper and Lower Silurian species. A further study 
of these sections should throw some light upon the Maine faunas. 
1 Description of new species of fossils from the Silurian rocks of Nova Scotia, by James Hall: Cana- 
dian Nat. and Geol., Vol. V, I860, pp. 11 1-151). 
