-2- 
River, while three other bream (RTLA 2387, 2389, 2390) had adeno- 
fibrosis; hepatocellular carcinoma, mesotheliomas and dermal fi¬ 
bromas in walleye, Stizostedion vltreum vitreum , (RTLA 2406-2408) 
and sauger, Stizostedion canadense , (RTLA 2409-2412) from Torch 
Lake, Michigan, which is rich in copper mine tailings and hepato¬ 
cellular carcinoma in freshwater drums, Aplodinotus grunniens , 
(RTLA 2413, 2414) from Lake Erie (all contributed by J. J. Black); 
hepatocellular carcinoma in Atlantic tomcod, Microgadus tomcod , 
(RTLA 2451, 2452; C. E. Smith) from the Hudson River; a cholangio- 
carcinoma in a brown trout, Salmo trutta , (RTLA 2442; N. C. 
Boustead) from the Eglinton River in New Zealand and hepatocellular 
carcinomas in brown bullhead, Ictalurus nebulosus , (RTLA 2504, 2513; 
P. Baumann) from the Black River in Ohio. These bullheads were from 
a series of 15 animals (RTLA 2501-2515) from the Black River which 
also had epidermal papillomas and carcinomas, plus cholangiocarci- 
nomas in the liver. The presence of hepatocarcinogens in this hab¬ 
itat has been documented {Baumann, P. C., W. D. Smith, and M. 
Riblck. Hepatic tumor rates and polynuclear aromatic hydrocarbon 
levels in two populations of brown bullhead (Ictalurus nebulosus ); 
in press}. Significantly, J. J. Black has induced liver and skin 
neoplasms in brown bullhead with extracts from sediment from another 
river which flows through a highly industrial area (RTLA 2594 — ac¬ 
cessioned in 1982). Workers in this field have now come full circle, 
having experimentally induced liver tumors with known carcinogens, 
having found liver tumors in animals from polluted environments and 
having experimentally induced liver tumors with an extract of sediment 
from a polluted environment. Therefore, evidence seems very strong 
that liver tumors in aquatic animals indicate the presence of carcino¬ 
gens in their habitats. 
Multiple, small foci of an epithelial neoplasm in the liver 
of a bonnethead shark, Sphyma tiburo , (RTLA 2549; W. H. Luer and 
C. A. Luer) was not clearly of hepatocyte origin. Foci appeared 
to be in vessels suggesting a metastatic origin from some glandu¬ 
lar organ such as the kidney, but no kidney lesions were seen at 
autopsy. Clearly of kidney origin, however, was a nephroblastoma 
in a rainbow trout, Salmo gairdnerl , (RTLA 2372; C. E. Smith) and 
a renal adenocarcinoma in a leopard frog, Rana pipiens , (RTLA 2373; 
J. C. Streett). Differential diagnoses of a visceral neoplasm in 
a puff adder, Bitis arletans , (RTLA 2377; G. E. Cosgrove) are 
metastatic renal adenocarcinoma and carcinoid tumor. 
Among epithelial neoplasms not already mentioned, are 
adenocarcinomas of thyroid in a kelp bass, Paralabrax clathratus , 
(RTLA 2379; G. C. Blasiola, Jr.), of the glottis in a yellow rat 
snake, Elaphe obsolete quadrivittata , (RTLA 2380; E. Jacobson) 
and in intestinal submucosa of a redhorse sucker, Moxostoma sp., 
(RTLA 2415; J. J. Black); an ovarian cyst adenoma in a blue- 
tongued skink, Tillqua scincoides , (RTLA 2475; A. Heldstab); and 
a transitional cell carcinoma of olfactory sacs in a black bullhead, 
Ictalurus melas , from the final oxidation pond of a sewage treatment 
plant (RTLA 2471; J. Grizzle). Another bullhead from this pond, 
RTLA 2470, had an epidermal papilloma. 
