Habits of the Crab 207 



they proceed much further from their burrows than usual. If 

 one endeavours to catch such a crab he either crouches quite close 

 to the ground, or tries to evade capture by looking for a burrow 

 sufficiently large to admit him. 



Larger elongated bits of sand about J/^ of an inch long were 

 observed gathered together in small heaps to a less extent, and it 

 was noted that these were produced by the crabs making their way 

 to the surface when the sand became uncovered by the receding 

 water, and also by the crabs deepening their burrows at intervals. 



Structural. 



A microscopic examination of the second maxillipedes shows 

 them to be bent upon themselves and to be fringed with hairs on 

 the inside and outside borders, these hairs being more densely 

 arranged on the former than on the latter. The hairs are of 

 different kinds. 



( I ) The first kind, as shown in the diagram, consists of a 

 central stem with small projections on each side, reminding one 

 somewhat of the structure of a feather. 



(2) The second kind is similar in structure to the first, but 

 differs from it in being shorter and in having the free extremity 

 shaped like the bowl of a spoon with notched borders. 



These two kinds i.e. (1 ) and (2) occur together on the inside 

 border of each second maxillipede and stand out almost perpen- 

 dicularly to the edge. The spoon-shaped kind is however par- 

 ticularly abundant on that surface of the maxillipede which 

 is applied to the body of the animal, i.e. the dorsal surface. 



(3) A third kind of hair is found on the outer edge of the 

 second maxillipedes and differs from the first kind in being longer 

 and in having the side projections more uniformly arranged. This 

 kind is curved strongly inwards. Hairs similar to those in the 

 diagram and simpler ones without side projections are found also 

 along the inner, and a few small ones along the outer borders of 



