FISHERY BULLETIN: VOL 76, NO. 1 



Figure 40. — a. Histological appearance 

 of early black gill lesion; note that black- 

 ening occurs first near tips of gill fila- 

 ments; normal gill filament (arrow) is to 

 right of blackened filaments. x580. b. 

 Histological appearance of advanced 

 black gill in cadmium-exposed pink 

 shrimp; note complete necrosis of gill 

 filaments, but clear line of separation 

 from more normal tissue below. x580. 



1972). Few studies have been reported concerning 

 effects of mercury compounds on penaeid shrimps. 

 Petrocelli et al.^^ studied the uptake and gross 

 distribution of mercuric chloride in brown shrimp. 



'^Petrocelli, S. R., G. Roseijadi, J. W. Anderson, B . J. Presley, 

 and R. Sims. 1975. Brown shrimp exposed to inorganic mercury in 

 the field. In Program of the first workshop on the pathology and 

 toxicology of penaeid shrimps. U.S. EPA, Gulf Breeze, Fla., 1 p. 



These authors also examined the effects of mer- 

 curic chloride exposure on ability of brown shrimp 

 to adjust to salinity changes. They found that after 

 2 h exposure to 0.5 ppb mercuric chloride in seawa- 

 ter, residue level of mercury in shrimp was 285 

 ppb with only d% of the mercury in the meat (mus- 

 cle) and Ql'/f in the shell. This suggested a surface 

 adsorptive process for mercury in brown shrimp 



34 



