No. 4.] DAWSON — POST-PLIOCENE. 397 



with our fossils. This species is probably the B. undatum of 

 Fabricius. It is allied to B. cyaneum, and may possibly pass 

 into it. (See Figure.) 



Buccinum tenue, Gray. 



Fossil — Riviere-du-Loup, not uncommon ; Greenland (Hayes) ; 

 Labrador (Packard). 



Recent — Murray Bay ; Gasp6 ; Labrador (Packard) ; Arctic 

 seas generally. A common Arctic species, but rare living in the 

 Gulf, though much more plentiful in the Post-pliocene beds. 

 (See Figure.) 



Buccinum ciUatum, Fabricius. 



Fossil — Montreal ; Riviere-du-Loup. 



Recent^ — Murray Bay ; Greenland (Fabricius) to Nova Scotia 

 (Willis). 



This is the original B. ciHatum of Fabricius, and has been 

 recognized as such by Dr. Stimpson. It is easily distinguished 

 by its narrow Nassa-like mouth, armed with a tooth on the front 

 of the pillar lip. It varies much in sculpture, especially in the 

 longitudinal ribs. The variety found at Montreal is only slightly 

 ribbed. That at Riviere-du-Loup is more distinctly ribbed, thus 

 resembling the recent specimens from Murray Bay. It is quite 

 distinct from B. ciliatiim, Gould, which is very near the smoother 

 varieties of B. wididatum. As it is a rare and little known 

 shell, I have figured two extreme varieties, a fossil specimen 

 from Montreal and a recent from Murray Bay. 



Buccinum glacicde, Linn. 



Fossil — Riviere-du-Loup; Montreal; Labrador; (Packard.) 

 Recent — Murray Bay ; Greenland, and Arctic seas generally. 

 This shell has the aperture somewhat like that of clliatum 

 and a very peculiar sculpture of spiral stri^ with intervening- 

 bands marked with finer strise. It has also a carina angulating 

 the body whirl, and sometimes more than one. In the latter 

 ease it passes into B. Gi^oeidandicum, Hancock (not Chemnitz) 

 or B. Hancockl Morch. The ordinary variety is most common 

 in the Modern Gulf, the latter in the Arctic seas and in the 

 Post-pliocene. This shell, usually much decorticated, is the most 

 common Buccinum in the Post-pliocence of Montreal. It was 

 called B. undatum in previous lists. 



