242 



Annals of the Carnegie Museum. 



Locality. — The writer has reported this species from Valcour Island, 

 but he is now doubtful whether it occurs there. It is common at 

 St. Martin Junction, near Montreal, at Caughnawaga and elsewhere in 

 Canada. 



25. Hebertella vulgaris sp. nov. 



(Plate XXXVI, figures 2-5.) 

 Orlhis perveta Billings, 1859. Canadian Naturalist and Geologist, Vol. IV, p. 434 



(mow Conrad). 

 Orthis siihcBquata Billings, 1859. Ibidem, p. 434 {non Conrad). 

 Orthis gibbosa Billings, 1859. Ibidem, p. 434 (non Billings, 1856). 

 Hebertella vulgaris Raymond, 1906. Annals Carnegie Museum, Vol. Ill, p. 501, 



et seq. Not described. 



Hebertella vulgaris is very closely allied to H. borcalis, but has a wider 

 shell and very much finer stria?. Young shells have a marked sinus 

 in the brachial valve, and it was such specimens that Billings identified 

 as Orthis perveta and Orthis gibbosa. The shells so identified by Billings 

 are now before me. The shell does not show a punctate structure, 

 and therefore can not belong to Dalnianella, as Orthis siibccquata, 0. 

 perveta and 0. gibbosa do. 



Fig. 15. Hebertella vulgaris Raymond. A large specimen, showing some 

 bifurcating striae. X 2. 



Fig. 16. The same species. A small specimen with direct strise. One-half 

 larger than natural size. 



Description. 

 Valves nearly equally convex, outline transversely oval, hinge of 

 variable length, but always less than the greatest width. Sides and 

 front rounded. Some specimens have a broad shallow sinus in the 



