PLEISTOCENE FOSSILS. 241 



Leda minuta. Fabricius. 



Fossil Leda clay, Montreal ; Riviere-du-Loup ; St. John, &c. 

 (Matthew) ; Greenland (Moller) ; Labrador (Packard). 



Recent Little Metis ; Kamouraska ; also British Columbia ; Arctic 

 seas, Gulf St. Lawrence ; coast of Nova Scotia. 



The fossil specimens occur abundantly with the last species at 

 Riviere-du-Loup, and are quite similar to those dredged at Murray 

 Bay. This was called L. caudata in my former lists. 



Leda pygmcea. Munster. 



Fossil Leda clay, Green's Creek, Ottawa ; Saco, Maine ; also 

 English Crag and other Glacial beds. 



Recent North European seas ; but not yet recognized on the 

 American coast. According to Mr. Jeffreys and Dr. Carpenter, our 

 drift-shells are referable to the variety or species Yoldia abyssicola of 

 Torell. 



Yoldia, (Portlandia) arctica. Gray. ( = Leda ylacialis, ante. ) 



Fossil Leda clay and Boulder clay, Montreal ; Quebec ; Ottawa 

 River; Riviere-du-Loup; St. John, N.B., &c. ; Portland and Saco, 

 Maine; also in Pleistocene of Norway (Sars), and of Scotland (Crosskey). 



Recent Arctic seas. 



This shell is most abundant, and generally diffused in the Leda clay ; 

 and the variety ordinarily found at Montreal and Riviere-du-Loup is 

 precisely identical with the ordinary Arctic form. A long variety, 

 called L. intermedia by Sars, is also found at Montreal, though rarely. 

 A short variety, common in the Pleistocene at Murray Bay, is 

 similar to the L. siliqua of Reeve from the Arctic seas ; and young and 

 depauperated varieties resemble L. sulcifera of the same author. The 

 abundant material from the Pleistocene shows that these are all 

 varietal forms. (Plate V., Fig. 4.) 



This shell is Yoldia arctica of Sars, but not of Moller and Morch. 

 It is Y. truncata of Brown. It is Portlandia glacialis of Gray, and 

 Leda Portlandica of Hitchcock. 



Yoldia lucida, Loven (which is abundant living in the deeper parts 

 of the Gulf of St. Lawrence) resembles the young form of this species, 

 but the two are probably quite distinct. J. F. W. 



Yoldia limatula. Say. 



Fossil Leda clay, Riviere-du-Loup. Yoldia sapotilla is recorded 

 by Matthew from Black Point, N.B. 



Recent Little Metis ; Gulf St. Lawrence to Long Island. 

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