ART. 4 CAMBRIAN CONCHOSTRACA — ULRICH AND BASSLER 109 



Plate 2 



Page 



Figures 1-4. Bradoria robusia (Matthew) (see also pi. 1, figs. 1-5) 22 



1. A well-preserved right valve, X 4. 



2. Enlarged view of the same specimen, X 8, showing 



particularly the surface sculpture. 



3. Two valves, X 4, in position. 



4. A right valve, X 4, differing slightly from the usual 



outline. 

 Lower Cambrian (Etcheminian E2a) : Dugald Brook, 

 Nova Scotia (13^, 13d). 



5. Bradoria robusta longula, new variety 24 



A left valve, X 6. 



Lower Cambrian (Etcheminian E16); Dugald Brook, 

 Nova Scotia (130- 



6,7. Bradoria benepunda {Matthew) 18 



(See also pi. 1, fig. 16; pi. 3, fig. 7.) 



6. A left valve, X 4. 



7. Enlargement of the same, X 6. 



Lower Cambrian (Etcheminian E3d) : Dugald Brook, 

 Nova Scotia (13n")- 

 8, 9. Bradoria benepunda spissa, new variety 18 



8. A left valve, X 4, preserving the crowded surface 



punctae unusually well. 



9. A smaller left valve, X 4. 



Lower Cambrian (Etcheminian E26) : Dugald Brook, 

 Nova Scotia (102:>). 

 10,11. Hipponicharion confluens, new species 64 



10. Photograph of the type specimen, a right 



valve, X 5. 



11. Drawing of the same specimen, X 12, exhibiting 



the confluent ventral ridge. 

 Middle Cambrian (Johannian C261) : West of Marion 

 Bridge, Cape Breton, Nova Scotia (3i). 



12. Hipponicharion plicatum, new species 64 



A left valve, X 5, exhibiting the subtriangular outline 



and the vertical folds of the surface. 

 Middle Cambrian: McNeil Brook, Cape Breton {3h). 



13. Hipponicharion parvum, new species 



Middle Cambrian (Johannian C26) : West of Marion 

 Bridge, Cape Breton, Nova Scotia (3i). 

 14-16. Hipponicharion minus (Matthew) (see also pi. 7, fig. 30)-- 63 



14, 15. Two left valves, X 6, exhibiting slight vari- 

 ations in outlines. ... 



16. A right valve, X 6. 



Lower Cambrian (Hanfordian Protolenus zone, C163): 

 Hanford Brook, New Brunswick (2i). 

 17-20. Hipponicharion matthewi (Wiman) 63 



17. Two valves of the carapace still in position, X 4. 



18. A right valve of the same specimen, X 4. 



19. A larger left valve, X 4. 



20. A right valve, X 4 (17-20 after Wiman). 



Lower Cambrian (Middle?), Glauconite sandstone: 

 Eggegrund, Sweden. 



