Crabs, Lobsters, etc. 



more in the way of burrowing than simply to sink into 

 the sand till they are sufficiently covered to be out of 

 sight of their enemies. Of these species, by far the most 

 interesting is the masked crab, a wedge-shaped creature, 

 well adapted for pushing its way beneath soft sand. 

 More interesting than the general contour of the masked 

 crab is the form of its antennae ; they are particularly 

 long and stiff; moreover, each antenna bears a double row 

 of bristles on its inner face. When the antennae are 

 placed together side by side the four rows of bristles meet 

 and, to all intents, the two antennae form a long tube. 



Now this tube is of the greatest use to the crab, as 

 it lies buried in the sand. The two antennae, placed 

 together, are pointed upwards towards the surface of the 

 water, and thus their owner, though itself in sand-laden 

 water, is enabled to draw clear water, from which it obtains 

 air to breathe, down its self-made tube. But this is by 

 no means the only use of the antennae. When the female 

 crab lays her eggs, after they hatch she passes the young 

 up between the antennae to the purer layers of water 

 above. A North American crayfish, which has taken to 

 life on land, burrows deep in the soil till it reaches the 

 water below the surface. During its excavations this 

 creature throws up substantial chimneys of mud at the 

 entrance to its burrow, with what object is not known. 



As the creature best able to suit the colour of its coat 

 to its surroundings most people would award the palm 

 to the chameleon. It may not be generally known that 

 a quite common little shrimp of our sea coasts runs the 

 chameleon very close in this respect. This curiously shaped 

 little crustacean, by reason of its build, has earned the 

 name of hump-backed shrimp. When it lurks beneath 

 brown seaweed it is brown coloured ; amongst green 

 seaweed its coat is green ; red seaweed as a background 

 causes the little fellow to turn red in sympathy. By night 

 he turns decidedly paler in colour, whatever his hue may 

 have been at departing day. 



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