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PACIFIC SCIENCE, Vol. XX, April 1966 
FIG. 3. Map of Moreton Bay, Queensland, showing localities at which field observations were made. 
stalks and mouthparts by vigorously rubbing 
the chelae over these regions. Cleansing is facili- 
tated by vibratory movements of the third max- 
illipeds and by alternate raising and lowering of 
the eyestalks. Sand on the carapace is removed 
as a result of a "back-flip” manoeuvre. This is 
essentially a half somersault and is executed in 
less than a second. The crab falls backwards, 
lies with the carapace on the substratum, and 
then flips back to the normal resting position. 
3. Preliminary Feeding Phase 
Subsequent to emergence the crabs feed and 
walk alternately, the feeding rate being much 
