LYMN^EIOE OF NORTH AMERICA. 



439 



one to eight are very uniform in oronensis; the ninth lateral has a 

 small indication of an entocone, the tenth and eleventh teeth are typi- 

 cal intermediates with well-developed entocone and ectocone ; the 

 twelfth tooth has usually a bifid entocone, while the thirteenth tooth 

 is a normal intermediate. The fourteenth tooth and all which fol- 

 lows are typical marginals, with irregularly serrated margin ; the meso- 

 cone persists in a few marginals, but all of the cusps become sub- 

 equal at about the seventeenth tooth. 



GENITALIA : Not examined. 



RANGE: (Figure 49). Maine to eastern Ontario. A species of 

 the Canadian and Nova Scotian regions and of the Boreal (Canadian), 



Distribution of 



QALBA ORONENSIS 



GALBA BINNEY1 



FlG. 49. 



Transition and Upper Austral life zones ; it is confined to the Atlantic 

 drainage. 



RECORDS. 

 UNITED STATES. 



MAINE: Lincoln, Penobscot River, Penobscot Co. (Bost. Soc. N. H.) ; 

 Orono, Penobscot Co. (Bolles; Stearns; Walker); Lake Auburn, Androscoggin 

 Co. (Lermond) ; Caribou River, Aroostook Co. (Nylander). 



BRITISH AMERICA. 



ONTARIO: Ottawa, Carleton Dist. (Latchford; Heron; Walker). 

 GEOLOGICAL DISTRIBUTION : Unknown. 

 ECOLOGY: Not differentiated from emarginata. 



