761 



Prod. 



also Salina and Shawneetown mines, Ind. Upper coal measures. 

 XV, 



Productus nebrascensis. Owen, Wisconsin Report, 1852, 



■^■^:?:?^i: 



Ind. 



1883. 



4A PRODUCTUS NEBRASCENSIS^ 



4 PRODUCTUS ME:,8RASCENSIS2 



4-8 PRODUCTUS NEBRASCENSIS 7 



yj. 









plate 5, fig. 3. Oollett's Indiana Rt., 1883, 

 page]22, plate 24, figs. 7, 8, 9, fi^^waZ 5?^^, 

 unusually perfect specimen. Common in the 

 Mississippi valley coal measures^ and frequent 

 in the Rocky mountains. Spines and outer 

 layer seldom recovered from its limestone 

 matrix; hence perfect shells from soft beds 

 look very unlike those got from limestone beds.— In W Penn- 

 sylvania it abounds in the Mercer lower and upper limestones 

 of XII, the Ferriferoiis limestone and Decker'' s creek shale of 

 XIII, the Brush creek, and Pine creek limestones, and Green 

 and Black cronoidal limestones of XIV. (See the various L 

 Q, and K reports.) In Eastern Pennsylvania it is described by 

 Mr. Heilprin in several fairly well preserved specimens of the 

 collection of Mill Greek limestone fossils in the Museum of the 

 Wyoming Hist. Soc, Wilkes- Barre, although the dorsal valve 

 is more prominently pustulated (like the English Productus 

 pustulosus, Phillips.) Geol. Sur. Pa. An.Rt. 1885, pages 440, 



