859 



Rens, 



Vanux- 

 em, Geol. 



Third 



Dist. N- 



Y., 1842, 



page 123, 



fig. 28, 2; 



Atrypa 



elongata. 



Hall, 



Geol. 



Fourth 



Dist. N. 



Y. 1844, 



page 148, 



fig 59,2; 



Megan- 



teris ovoides, Hall, 1856, 1857; Rogers, Geol. Pa., 1858, 

 page 826, fig. 649; R, ovoides, Hall, Pal. N. Y. Vol.3, p] ate 104, 

 fig. 4, giving a good idea how colonies of these shells were 

 piled up in the sandy deposits of the Oriskany, VIL Geol. 

 Canada, 1863, fig. 470, a ventral valve. In Pennsylvania on 

 the Delaware river, found in White's Oriskany shales (G6, p. 

 123,124.) In Huntingdon Co., vast numbers occur in spots 

 along the Sand Ridge east of Mapleton (T3, p. 274; 000, p. 



Ha/f. 



