105 



"^^^^^^^^fe^^ 



CRI5TIANSB0RG 



NAUTICAL MILE' 



Fig. 28. Illustration of the patchiness of community distribution in the nearshore "fine sand" 

 community off Accra, Ghana, from Buchanan (1958). 



Studied in detail, especially where salinities, temperatures, and bottom 

 types appear fairly uniform. It is possible that here the biological factors, 

 such as competition, feeding types, larval development, etc. are more 

 important in limiting the composition of small communities than the 

 physical-chemical factors. 



The nearshore, 11 to 26 meter region, with its almost uniform sand 

 bottom, provided an opportunity to check the effectiveness of the grab 

 sampler as opposed to the shell dredge in appraising the quantitative 

 aspect of bottom communities. As mentioned previously, the depths of 

 between 11 to 26 meters appear to be the most prolific in species of all 

 environments studied in the Gulf of California, resembling somewhat the 

 Venus community of British and Danish waters (Ford, 1923). Whether 

 this diversity compares quantitatively with other regions in the world 



