246 DAHLAK 



Decapo da brachiura 



While the macrura group, at least in our experience, is not 

 readily observable in the Red Sea (because of its habit of 

 hiding in the inner cavities of the madrepore) the brachiura 

 or crab group is well represented and is common in coral or 

 sandy waters. Crabs are also found on dry beaches and even 

 in inland regions where the vegetation begins to be sparse and 

 arid. These Crustacea are the famous pyramid crabs [Ocypoda 

 cerathophthalma) , whose distinguishing features are long legs, a 

 yellowish red colouring and strongly pedunculated eyes, 

 which are elevated at any sign of danger and are swivelled 

 like two periscopes. Like the prawns just mentioned, these 

 crabs dig their holes in the sand, although in dry zones. 

 They excavate with their claws, depositing the sand near the 

 entrance hole. The sand is heaped up into cones of about a 

 foot high. These are not found on all the beaches, however. 

 It may be that the consistency of the sand in some areas 

 does not allow this and the crabs dig their holes without 

 worrying where and how the excavated material is dumped. 

 The ocypoda likes the company of human beings. There 

 is, of course, an ulterior motive; where there are no mice, or 

 very few, the crab takes their place. The mice were in fact 

 more forebearing and were satisfied with robbing us of what 

 they needed for the meal of the day. But the ocypoda was 

 more presumptuous. Besides removing any provisions within 

 the grasp of its big claws, it lifted things that were anything 

 but edible, such as pencils, fountain pens and even the bright 

 tube of lip-stick belonging to the young lady of the party. 

 We did not censure him too severely for this latter theft. In 

 the place and circumstances it was difficult to decide whether 

 the object was of more use to him or its lawful owner. 



