Bull. U. S. B. F., 1927, Pt. II. (Doc. 10.31.) 



Tig. 32.— Amount of fouling accumulating within 60 days (May 15 to July 16, 1926) on a board 4 inches wide by 1 inch 

 thick and 26 inches long. A, entire board, indicating average low tide line (x); B and C, enlarged views of growths 



