0 = Dead. 
1- = An oyster that is completely transparent is definitely un¬ 
healthy, all organs clearly visible (no gonad or glycogen). 
It does not fill its shell cavity but lies like a limp 
piece of clear gelatin on its valve. This oyster is mori¬ 
bund . 
1 = Same as above with slight nuances for improved scoring. 
This oyster may live. 
2 = Oyster not transparent but liver (digestive gland) clearly 
visible. Gonad or glycogen low and patchy. Does not fill 
its shell cavity well. Not moribund. 
3 = Average looking. Reasonable amount of gonad and/or glyco¬ 
gen. Liver barely visible. Mantle appears to be an active, 
well-functioning organ. If examined immediately after col¬ 
lection a crystalline style may be found. 
4 = Good looking. Enough "fat" to cover liver completely. 
Plumper than 3, therefore, fills its shell cavity shell. 
Mantle uniform rich color. Mantle edge active to stimu- 
lae. Healthy heartbeat. Solid crystalline style upon 
examination immediately after collection. 
5 = Excellent looking. The oyster appears cramped by its 
shell cavity. It bulges over the half shell with thick- 
layers of gonad and/or glycogen. Clean uniform coloration 
throughout. No deficiencies of any kind noted. 
Upon completion of this gross examination, the oyster meats 
were individually wrapped in cheesecloth together with a num¬ 
bered tag for later identification and preserved in Davidson's 
fixative. 
Data for new growth and mean condition score were compared 
using Student's t-test. 
Possible Point Source Studies 
A 96-hour toxicity study was performed at stations in the 
vicinity of possible point sources of pollution. These sources 
were the Chestertown Sewage Treatment Plant, the Tenneco chemi¬ 
cal plant which manufactures plasticizers and the Campbell's 
Soup Company where chicken carcasses are prepared and diced. 
Tenneco and Campbell's discharge into Morgan Creek while the 
Chestertown Sewage Plant discharges into Radcliffe Creek shortly 
before it joins the Chester River at the southern edge of Ches¬ 
tertown . 
19 
