Bull. U. S. B. F., 1917-18. 



PLAT15 XIX. 



Yellow sand-shell, Lampsilis anodontoides (Lea), from :Mis3issippi River. (See p. 3 1 . ) 

 telougn sand-shell, Lampsilis fallaciosa (Smith) Simpson, from ]Mississippi River. (See p. 32.) 

 UlacJc sand-sh ejl, Lampsilis recta (Lamarck), from JMississippi River. (See p. 32.) 

 , Lampsilis subrostrata (Say), from JMississippi River. (See p. 32.) 



