110 THE CANADIAN NATURALIST. [Vol. viii. 



Mytilus edulis, Linn. — Recent,Greenland to Long Island Sound 

 — Littoral. — Fossil, R. C, R. B., St. J., St. A. Common in 

 upper beds of the Leda clay at St. John ; and is plentiful on 

 Bay Chaleur where var. elegans is common. 



Cryptodon sp. ? — Fossil St. John. Rare. Specimens of 



a Cryptodon quite different from C. Gouldli, Phil., are to be 

 found occasionally in the starfish beds of Duck Cove : it is near 

 C.flexuosus of the British seas, but differs in being more tumid, 

 especially toward the beaks, and these are more sharply curved 

 at the points than those of the British species named. The fur- 

 row extending from the beak toward the posterior margin of 

 our shell is much narrower than in C.Jlexuosus ; and the ridge 

 dividing it from the ligamental border is correspondingly nar- 

 rowed and sharpened. There is a faint ridge descending 

 from the beak to the base of the anterior border, and between it 

 and the lunule, the concentric wrinkles of the epidermis are 

 stronger. Shell thin and fragile. Epidermis pale yellowish 

 blown. 



Kellia suborbicularis, Montagu. — Recent, N. Europe, (Nova 

 Scotia and Massachusetts Bay, Gould.) Fossil at Black Point. 

 Rare. A small shell, which agrees with the figure and descrip- 

 tion of this species in Gould's Invertebrata of Massachusetts. 



Serripes Groenlandica, Chemnitz. — Recent, Greenland to Mas- 

 sachusetts Bay.— Coralline.— Fossil R. C, R. B., T. R., St. J., 

 St. A. Recent individuals from Mingen River, Labrador, are 

 double the size of our largest shells from the Post- Pliocene. 

 Shells from the clays of the Bay of Fundy are thin and 

 fragile. 



Cardium pinnulatum, Conrad. — Recent, Gulf of St. Lawrence 

 to Long Island Sound. — Laminarian. — Fossil, St. J., St. G. 

 Rather plentiful in a few places. These shells, especially the 

 larger ones, are more angulated than the recent individuals from 

 Mass tchusett's Bay figured by Dr. Gould. 



Astarte arctica, Moller, var. lactea ? — Recent, Greenland to 

 Casco Bay, Maine. — Fossil at St. Andrews where it is infre- 

 quent. This is the largest of our Astartes ; it is wider than A. 

 semisulcata, Gray, and possesses a beak which is nearer the 

 anterior margin and more acute. 



Astarte compretsa , Linn. — Recent, Greenland to Labrador. — 

 Fossil at St. Andrews. Infrequent. This is intermediate in form 

 between the last and the following species ; it is a deeper, higher 

 and thinner shell than A. lactea. 



