17 



Aug. 27. Sept. 27. Aug. 27. Sept. 27. 



Length cm. Length cm. Length cm. Length cm. 



1 1.7 2.3 II 2.4 3.2- 



2 2.1 3.3 12 2.4 3.2 



3 3-5 3-5 13 1-6 2.0 



4 3-3 4-1 14 4-5 47 



5 9 1-8 15 2.2 Z.2 



6 4.0 4.6 16 2.4 3.4 



7 31 3-6 17 1-8 3-0- 



8 3.6 4.1 18 2.5 3.4 



9 37 4-5 19 3-1 3-S 



10 1.7 2.6 20 4.4 0.1 



According to these observations the average increase in length 

 in 30 days was .76 cm. If oysters grew at this rate in older stages 

 they would reach a marketable size of 3.7 inches in a year, but as 

 growth takes place more slowly with advancing age one year 

 would be too short, though two years, with a favorable supply of 

 food might well be long enough.* If this prove true Louisiana 

 oysters under favorable conditions grow faster than those in 

 northern waters, a fact which might be expected from the differ- 

 ences in the rate of growth exhibited by northern reefs. Thus 

 Moore (Manual of Fish Culture, P. 275) states that "in South 

 Carolma oysters not more than 6 ox "j months old were found to 

 have reached a length of 2^ inches, and in the warm sounds of 

 North Carolina they reach a length of i^ inches in from 2 to 3 

 months. In the coves and creeks of Chesapeake Bay they attain 

 about the .^ame size by the end of the first season's active growth, 

 and by the time they are two years old they measure from 2^ to 

 2,}% inches long and from 2 to 3 inches wide. On the south side of 

 Long Island the growth of the planted oysters is much more rapid 

 than in Connecticut, it being stated that "two-year plants" set out 

 in spring are ready for use in the following fall, while upon the 

 Connecticut shore it would require 2 or 3 years to make the same 

 growth. On the south side of Long Island, oysters i^ inches long 

 in May have iticreased to 3 inches by November of the same year." 



These cbseivations on the new stock of the natural reefs give 

 good groiir.c's for the hope that in two years from the date of th'* 



♦These observations were sugeested by the fact that a certain enthuslastif mem- 

 ber of the State Oyster Commission had oo exhibition a five inch oyster said to be 

 one year old. While my measurements do not show that such phenomenal growth 

 may not take place under exceptional conditions, they do show that 5 inches of 

 growth during the first year is not general. 



