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BULLETIN OF THE BUREAU OF FISHERIES 
(3) Thermograph records of water temperature in the bayou show that at the end 
of February the winter temperature was 14° to 15° C., while during the spring and 
summer it rose to between 30° and 33° C. 
(4) Because of increased river discharge in spring and early summer the salinity of 
the water in Galveston Bay remained low for a considerable time. In early spring the 
salinity in the bayou was 22 to 24 parts per thousand, while early in June it was down 
to 7 parts per thousand. At the same time in West Bay it was only 4 parts per 
thousand. In East Bay late in June it was below 2 parts per thousand. During July 
and August the salinity rose to between 20 and 30 parts per thousand. 
(5) The characteristic pH of the water in Galveston Bay was between 8 and 
8.4, fluctuating between these levels. In August in the bayou it rose to 8.9. 
(6) Setting was irregular and took place during short, isolated periods. The 
first spat were not obtained until a month and a half after spawning started. 
(7) In Offatts Bayou two chief setting periods occurred, one at the middle of 
May, and the other beginning at the end of August. In addition two very light sets 
were obtained at one place in the bayou; at the end of May and at the beginning of 
July, respectively. 
(8) In West Bay at the Deer Islands two setting periods were observed; a short 
one early in July, and a more prolonged one beginning at the first of August. At the 
latter time setting was very heavy and up to 3,500 spat were obtained daily per bag 
of shells. 
(9) On Hanna Reef, East Bay, a light set was obtained at the beginning of May 
and a fairly heavy one at the end of July and first part of August. 
(10) The setting periods appear to have been correlated with periods of high 
salinity, suggesting that in some manner the larvse depend, either directly or second- 
arily, upon a salinity above about 20 parts per thousand, in order to develop to the 
setting stage. 
(11) Most of the larvse taken in the collections were in the straight-hinge stage, 
with the exception of short periods, until August when many umbo larvse were taken. 
It is probable that setting was not more continuous because early in the season few 
reached the setting stage. 
(12) Of 252 adult oysters from different reefs only 51 were males and 178 were 
females. The remaining 23 specimens were either too completely spawned out or 
immature to permit ready determination of sex. 
(13) Diatoms in the surface plankton collections were most abundant in early 
spring and slowly decreased in numbers taken so that in July and August the water 
was almost free of them. It was observed that during periods of low temperature 
of the water more diatoms were taken than during times of high temperature. This 
was the case for temperature changes occurring over a few days as well as over the 
entire period during which collections were made. 
(14) Use of wire bags of shells as cultch was tested in Galveston Bay waters 
and found to be highly satisfactory as a means of collecting spat for developing 
oyster grounds. 
LITERATURE CITED 
Battle, John D. 
1892. An investigation of the coastal waters of South Carolina with reference to oyster culture. 
Bulletin, United States Fish Commission, Vol. X, 1890 (1892), pp. 303-330, 7 charts. 
Washington. 
