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GROWING PERIOD (months) 



FIGURE 17. CALCAREOUS TUBEWORM GROWTH 



The curves of average and maximum lengths of tubeworms (Fig. 17) 

 are somewhat more irregular, although the average curve shows a 

 definite increase and then a gradual leveling off with time. The wide 

 variation in these plots results from the extreme difficulty encountered 

 in measuring the length of the tubes which are typically meandering 

 or convoluted. 



Figures 18 through 20 are photographs of panels after thorough 

 drying. The sequence of pictures of the 1-month panels (Fig. 18) 

 shows quite clearly the seasonal progression of biological activity. 

 Photographs of the convex side only are shown; the concave side of 



22 



