118 
Fic. 35. 
Pathologi 
ILLINOIS BIOLOGICAL MONOGRAPHS 
EXPLANATION OF PLATE 
Amblema undulata. Left valve with channel due to injury. 
Amblema undulata. Right valve with ridge due to same injury. 
Strophitus edentulus. Right valve with pearl near posterior end. 
Strophitus edentulus. Left valve with distomid discoloration. 
Lasmigona costata. Right valve with repaired injury near posterior end. 
Amblema undulata. Spoon River form with rounded shell. 
Lampsilis ventricosa. Left valve with injured postero-ventral margin. 
c mussels from Salt Fork. 
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