NUCUL. 



476 



Nuculites 



? In Hamilton shale near Union school- 



house, St. Olair, Bedford Co., Pa. T2, p. 129.— VIII c. 



Nuculites ? Sp. 883-8 (showing; crenulations of 



hinge line) from Tioga Co.,N. Y., in Chemung, VIII g. 



Obolella chromatica, Billings, Pal. Foss. Vol. I, 1861, 



Potsdam forma- 

 tion. W a 1 c o 1 1 , 

 Jour. A. S. Vol. 29, 

 Feb. 1885, p. 116, 

 reproducing Ford's 

 figures (Am. Jour. 

 Sci. Vol. 21, 1881, 

 p. 131.) Fig. 1, 

 plan of interior of 

 /FHi. dorsal valve; fig. 

 2, ditto of dorsal valve. 

 Geol. Can. 1863, page 

 ^^ 284, fig. 288, a, ventral 

 -^5Il?5'^: JMh^ valve ; 5, dorsal ; o, in- 



terior of ventral? with muscular scars; d, outline restored 

 from detached valves. (The two figures 239 ^, Z>, are of Olo- 

 lella pretiosa. which see below.) Quebec group ^ called ^^ Pots- 

 dam " by Logan. L Walcott's Bull. 30, U. S. G. S. page 112, 



plate XI, fig. 1, dorsal valve ; fig. 1 a, ventral valve ; fig. 1 J, 

 interior of dorsal valve ; all three enlarged about three times. 

 Inserted small figs. 9 and 10, are from page 110, describing the 

 genus Obolella, — Lower Cojmbrian formation, at L'Anse on 

 Loup, Straits of Belle Isle (north side). — (See Billings, Geol. 

 Vt. 1861, pi. 2, figs. 346 a to d, 1861 ; Geol. Can. 1863, figs. 288 

 aio^d; Pal. Foss. 1865, pi. 1, figs. % aio^d; A. J. S. 1876, p. 

 176, figs. 1 to 4 d See also Ford, 1881, in A. J. S. Vol. 21^ p. 

 133, figs. 3, 4.)— Z. G, 



