28 



MEMOIRS OF THE CARNEGIE MUSEUM. 



Outside of Pennsylvania this species has been recorded only from those states 

 which border on Lake Erie. It is known from Buffalo, New York (Marshall, 

 1895, p. 50), but said to be identical with U. undulatus {= A. c.ostata). It is given 



Fig. 4. 

 • Amble7na plicata. 

 ■ Amblema plicaln costata. 



from the Ohio shores of the lake by Sterki (1907a), and from the shores in south- 

 eastern Michigan (Walker, 1898), and from Lake Erie in general (Walker, 1913). 

 The record from Lake Winnipeg, Canada (Hanham, 1899) should be questioned 

 for the present.^- 



Amblema plicata costata (Rafinesque) (1820). 



Quadrula undulata (Barnes) Simpson, 1914, p. 819;-'' Quadrula costata (Rafin- 

 esque) Vanatta, 1915, p. 556; Amblema -plicata costata (Rafinesque) 

 Utterback, 1916, p. 33. 



Plate II, fig. 7; Plate III, figs. 1, 2, 3. 

 Records from Pennsylvania: 



Clapp, 1895 (Allegheny Co.)- 



Marshall, 1895 (Allegheny River, Warren Co.).-* 



Rhoads, 1899 (Oliio River, Beaver Co., and Beaver River, Wampum, La\vi-ence Co.) (a.s jdicatus). 



Ortmann, 19096, p. 198. 



=- Simpson (1900, p. 769, footnote .3) mentions a peculiar form of " undulata " from Lake Winni- 

 peg. Possibly this is the same as that referred to by Hanham, and might be a form parallel to plicata. 



^ Simpson makes a singular mistake in quoting, among the synonyms, Unio undulatus Sowerby, 

 1868, PI. 76, fig. 399, which probably is Alasrnidonta undulata (Say). 



" I did not find this form so far up in the Allegheny, but only as high up as Venango Co., where it 

 is very rare. But it may have extended farther up in the past. 



