SPAWNING AND SETTING OF OYSTERS 
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The first oysters which were found to be somewhat “milky ” were taken on March 
18 in the bayou. Only an occasional specimen, however, contained either well- 
formed eggs or active sperms. On March 23 a similar condition was found in 
Figure 6.— Showing approximate size and relative abundance of oyster larvse in plankton samples taken in 
Offatts Bayou, April to August, 1929. Size range of larvaB in microns of shell length is shown as vertical 
lines corresponding to values of ordinates shown on left of graphs. Relative abundance of larvse was 
estimated as follows: 0, none; 1, very few; 2, few; 3, fair number; 4, many; 5, very many. Larvse 150 
microns or more in length are in umbo stage and closely approaching maturity 
oysters taken from both East and West Bays. On the 29th all specimens from the 
bayou which were examined contained mature eggs or sperms, and some appeared to 
have spawned partially. On April 5 specimens from East and West Bays also 
appeared to have started spawning. 
