439 



Naiad. 



DlCriOXA.KY 



OF 



FOSSILS FOUND IN PENJSrSYLYANIA 



AND ELSEWHERE. 



Volume 2. 



Naiadites, Dawson's name to include the lamellibranch 



J 



/M, Fig, 42. 



Fis. 43. 



Fig. 44, 



Fig. 45. 



Modiolas^ Unios^ Anodons^ of other authors. Seven of 

 these occurring in the Coal Measures of Nova Scotia, he 

 names iV. {Anthracoptera) carhonaria^ f. 42 ; N. {Anthracomya) 

 elongata. f. 4:3 ; ]V. { Anthracoptera) loevis, f. 44; iVi arenacea^ 

 f. 45 ; N. ovalis ; N. angulata^ f. 46 ; N. ohtusa ; Salter giving 

 them the names in parenthesis. Giimbel and Geinitz say 

 Dreissena carhonaria. King's Anthracosia occurs in Nova 

 Scotia only in the Lower Coal of Baddeck, C. B. Naiadites 

 have both thick and thin shells; an external ligament; no 

 teeth; have not been found in strictly marine limestones, nor 

 in company with proper marine shells, and were probably 

 attached by a byssus to sunken or floating timber; probably 

 were all brackish or fresh water shells, like the Mytilidce and 

 embryonic JJnionidm. Dawson's Acad. Geol. 1868, p. 204. 

 1 



