Ling. 



342 



3Et.3a» 



Lingula acutirostra, Hall. Eeport on Fourth District of 

 V. A^ New York, 1843, page 76, fig. 18, 9; a shell of the 

 Clinton formation^ readily distinguishable from all 

 other New York lingular ^ by its acute point ; surface 

 H-l?^^ 9 marked by a single series of rather course striae ; larger 

 X\\c\\\ L acuminata^ and striae stronger. — Y a. 



Ling-ula aequalis, Hall. (Pal. N. Y., Vol. 1, 1847, Tren- 

 ^ ton.) Emmons, Amer. Geol. Vol. 1, part 2, 1855, 

 p. 203, plate 8, figs. 3<^, 35, closely resembling Lin- 

 gida riciniformis. — Trenton formation^ II c. 

 Em.A-t% . nS 



Lingula ampla, Owen. Geol. Wis., Iowa and Minnesota, 



1852, plate IB, fig. 5, 

 12; from the Lingula 

 grits^ upper Missis- 

 sippi river near Moun- 

 tain island, supposed 

 to be the western ex- 

 tension of the Pots- 

 dam sandstone — /. 



Lingula antiqua, with L, prima^ Owen. GeoL W., I. and 



,^2^^ Minn. 1852, pi. 1 B, f. 2, 7, 10, from the 

 St Croix (Potsdam) sandstone at the 

 falls of the St. Croix river ; specimens 

 usually much larger than those of the 

 New York Potsdam. — Emmons, page 

 268,fig. 68. Po^56?am formation. (Rog- 

 ers, pp. 815, 816, says that it somewhat 

 resembles Z. curta^ ^^o.) — /. 

 Lingula centrilineata, Hall, 1859, Pal. N. Y. Vol. 3, Low, 

 Held, Olaypole's list (doubtful), VI — See Appendix, 



