COASTS VISITED BY THE ARCTIC EXPEDITION. 597 



good throughout Europe, wherever the Upper Silurian and Devonian 

 series are represented. It is abundant everywhere in Canada, North 

 America, and the American Arctic rocks, Scandinavia, Russia, 

 Bohemia, and even in Australia, occurring in all stages of the 

 Upper Silurian series, and culminating in the Devonian. Sixty-two 

 species occur of the genus Atrypa in the State of New York alone. 



Log. Cape Hilgard, lat. 79° 41'; Dobbin Bay lat., 79° 40', &c. 

 Upper Silurian. 



Genus Steophomena, Rafinesque, 1825. 



Steophomena euglypha (Hisinger). 



Leptcena euglypha, Hisinger, Anteckn. t. 6. f. 4. 

 Strophomena euglypha, Salter, Siluria, t. 20. f. 9 ; Dav. Monogr. 

 Brit. Sil. Brach., Pal. Soc. p. 288, t. 40. f. 1-5. 



This abundant shell in the British Upper Silurian series is now 

 determined to be present in rocks of the same age in the Arctic 

 regions ; it has been found both at Cape Hilgard and Cape Louis 

 Napoleon in beds which contain many Wenlock species. There is 

 no doubt of this shell being the above species. We wonder no more 

 specimens have occurred, considering its ubiquity and wide range, 

 being common in the Llandoverj^, Wenlock, and Ludlow formations 

 of Britain and of the north of Europe. 



Loc. Cape Hilgard, lat. 79° 41', and Cape Louis Napoleon, lat. 

 79° 38'. 



Steophomena siltjriana, Dav. 



Strophomena siluriana, Dav. Monogr. Brit. Silurian Brach., Pal. 

 Soc. p. 303, t. 47. f. 1-4. 



I cannot see any difference between our single specimen and Mr. 

 Davidson's figure. Ours is the ventral valve ; none of the hinge-area is 

 exposed ; and although the horizon of Mr. Davidson's species is some- 

 what lower or older than that of our form may be, still in a species 

 so variable (especially, with age), and having only one specimen, it 

 is not well to be positive either as to stratigraphical position or actua] 

 species. 



Loc. Cape Leidy, lat. 79° 38'. 



Genus Meeistella, Hall, 1860. 



Meeistella ttjmida (Dalm.). 



Atrypa tumida, Dalm. Vet. Akad. Handl. 1828, p. 134, t. 5. 

 f. 3. 



Meristella tumida, Dav. Mon. Brit. Sil. Brach,, Pal. Soc. p. 109, 

 t. 11. f. 1-13. 



A large, but solitary, specimen occurs in the collection. Meristella 

 is abundant in the Upper Silurian rocks of both hemispheres, ranging 

 in Britain from the Caradoc to the Wenlock rocks, and occurring 

 in America in the Lower Helderberg, Clinton group, and Pen- 



