FRESH-WATER MUSSELS AND MUSSEL INDUSTRIES. 63 
An article in the Journal of Biological Chemistry, 1910, volume 8, page 237, by H. C. 
Bradley, on ‘‘Manganese in the Tissues of Lower Animals” gives analyses showing the 
proportion of manganese in the ash as taken from a group of nine samples of mussels 
from the Mississippi River. The high proportion of manganese, as compared with its 
occurrence in other animal tissues, is of unusual interest, but is without economic signifi- 
cance as now understood. 
ANALYSIS OF MUSSELS FROM THE MIssISsipPI RIVER SHOWING HIGH PROPORTION OF MANGANESE 
(Arter H. C. BRADLEY). 
Te Manganese | Manganese Total 
‘ in ash. in tissue. | nitrogen. 
Per cent. | Percent. | Percent. | Per cent. 
Marit ty, cates cea ceit apes bane thes ee seine. gk vechieeleuetntns + 08! aie bins 23.5 35 0. 823 7-37 
Wagaitrasaran Oe ec setae ecteetaeioaaoe ermine tae reat ie. = Mia acctelagas ol oetotatorsvas/aisie: Sain’e pininie's 13-5 37 » 500 7-37 
Aivera els PIS Te bts da. n Wintoielam «thd Gide bod chad vinta oe om Meholati dew Wiad hie 16.5 3-9 +63 7224 
UNDERSIZED SHELLS. 
The most serious waste in connection with the mussel fishery consists in the taking 
and killing of undersized shells. It is argued by some fishermen that the young mussels 
should not be thrown back, since a considerable proportion of the mussels taken by the 
crowfoot die when returned to the water. Several experiments conducted at the Fair- 
port Biological Station indicate that from 35 to 40 per cent of the mussels taken with the 
crowfoot and returned to the water die in a short time. However, careful counts of 
weights of shells actually taken in the mussel fishery and under 2 inches in greatest 
dimension show that it requires from 33,000 to 174,000 to make a ton, with an average 
of about 90,000. Should these mussels be returned to the water and should only one-third 
live to attain a size of 2 inches in greatest dimension, the surviving mussels would weigh 
much more than a ton, and would thus be of greater value to the fisherman than the 
entire original quantity marketed as small shells. They would yield a far greater number 
of buttons per ton, and thus would be of more value to the industry. Furthermore, the 
larger mussels would have spawned and taken part in replenishing the beds, and thus 
would have been of inestimably greater benefit to the conservation of the mussel beds. 
