375 



Macro. 



Macrodon hamiltoniae, Hall. 1870, Prelim. Notice Lam. 

 shells, Olaypole's list, Report F2, preface, p. xiv. Hamilton 

 formation, See Oat. 00, p. 231, specimen 5-62 (two) col- 

 lected near Barrett's mill, N. W. of Bloomfield, Perry Oo., Pa. 

 Multitudes of them occur in the Bedford shale of Ohio, which 

 is higher in the series. Eeport I, p. 73. — VIII c. 



Macrodon hardingi, Dawson. Acadian Geology, 1868, p, 

 XIII ^ \Q'> ^^ 302, fig. 102, «, medium 



sized cast of the inner sur- 

 face ; 5, outer surface ; (?, 

 3.:ivv -^^^^^^ >^ magniH^d sculpture ; shell 



thick, usually represented by casts of interior, smooth, with 

 deep scars ; outer surface covered with regular squamous con- 

 centric folds, fringed with delicate ray-lines; beautiful shell, 

 abundant (especially in Windsor bed e); characteristic of up- 

 per stages of Lower Cariomferous limestones. Allied to 

 Byssoarca reticulata^ M'Coy, Irish coal measures ; to Area 

 m?Goyana^ and anatina^ De Kon. of Belgium ; and to Bys8. 

 tumida of the Permian. Largest specimens 1^ inch long. — 

 XI? 



Macrodon obsoletus. Meek, Regent. Rt. Univer. Virginia, 

 1071 ; Geol. Ohio, Pal. Vol. 2, p. 334, pi. 19, fig. 

 9; recognized by Heilprin among the Mill 

 Creek limestone carboniferous fossils in the 

 museum of the Wyoming Hist. Soc, at Wilkes- 

 barre, Geol. Pa. An. Rt. for 1885, page 456, fig. 

 19 ; 1000' above the Pottsville Conglomerate 



No. XII. In Beaver, Lawrence, Mercer and 



Butler Cos. it occurs in the Ferriferous lime- 

 stone.^ not far above the Conglomerate. Q, 62; 

 « MACRODON oB«>LET«.. q^, 47 ; Q3, 25 ; V, 147. In Fayette Co. it 



occurs in the Crinoidal limestone of the Barren Measures, L, 35- 

 —XIII XIV. XV Note. For figure from Pal. Ohio, Vol. 2, p- 

 334, plate 19, fig. 19, ^ee Appendix, 



Macrodon? shubenacadiensis, Dawson. In Acadian 

 ^3 Geology, 1868, p. 303, fig. 103, a cast of the shell; 

 genus uncertain ; very common in Nova Scotia 

 and Cape Breton in Garioniferous lunestones. 



Daw.^^^i--^ XI f 



