Figure 4.2 



Pacific Oysters Collected in Oregon, 

 Demonstrating Abnormal Growth Effects. 



(A) Pacific oyster ( Crassostrea gigas) collected in South Slough, Oregon, 

 in March 1987, showing ball shape. 



(B) Upper valve of a Pacific oyster showing excessive thickness (top) and 

 chambering (lower) when sectioned. 



Source: Wolniakoski et al., 1983. 



IV-13 



