PLKISTOCENE F0SSIL8. 257 



Buci'inum glacidle. Linn. 



Fossil — Rivirre-tlu-Loup; Montreal; Anticosti; Labrailor (Packard); 

 Hlack Toint, X.IJ. (Matlhuw). 



Kucoiit— Murray l>ay ; Little Metis; Alaska (Dall) ; (ireenland, 

 and Aretic f c.is generally. 



This shell has the aperture somewhat like that of ciliatum, and a 

 very peculiar sculpture of spiral striae with intervening bauds inarkeil 

 witii liner striae. It has also a carina angulating the body wliorl, and 

 sometimes more than one. In the latter case it passes into B. Grain- 

 liiiidicinii, Hancock (not C'henniitz) or B. Ildxcocki Morcli. The 

 ordinaiy variety is most connuon in the modern (iulf, the latter in 

 the arctic seas and in the I'lcistoccne. This shell, usually nuicii 

 decorticated, is the most common l>uccn-inn in the I'leistocene of 

 Montreal. (See figures, plate L) 



Buccinum plectrum. Stimpson. 



Fossil— Kiviere-du-Louj) ; rare. 



Recent — Murray Bay ; Portland, Maine (Stimpson) ; liehring's 

 .Straits (Stimjjson) ; Alaska (Dall). 



This may l)e a variety of the preceding species, hut can be distin- 

 guished from it and grows to a larger size. It has the scidpture of 

 B. glacinle with the aperture of B. undui/itum. Recent and fossil 

 specimens are (juitfl similar. 



The northern Biirrina are involved in so much confusion that I 

 have made them a subject of special study, and have sedulously 

 collected all the forms recent and fossil. I have been very mucii 

 aided in this bj' the abundance of s[)ecimens of the more arctic forms 

 at Rivien -du-Loup, and the occurrence of most of them recent at 

 Murray Bay and Tadoussac, and I feel conti<lent that the names given 

 in this list represent; forms actually occurring as distinct in nature, 

 though some of them may not be distinct specific types. I believe, 

 iiowever, that B. ciliatum, B. glacinle, B. undulatum, B. tenue and 

 B. Granltindicum, are probably entitled to this rank. The others 

 appear to me, on comparison of large numbers of specimens, to graduate 

 into one or other of the above forms. 



I have given in the engraved plate representatives of the more 

 critical forms, which will enable them to be recognized. 



In the drift the Buccina often part with their outer coat of 

 prismatic shell, and in this decorticated state are very difficult to 

 determine. _.:.... 

 18 



