140 CRAYFISH, LOBSTERS, SPIDERS, AND INSECTS 



Spider crabs. — The spider crabs are curious-looking 

 creatures (Fig. 80) with their small bodies and long, slender, 

 fragile-looking legs. For the most part they frequent the 

 sea bottom, and their long legs are of great advantage in 

 stalking about over the uneven surfaces that they meet in 

 such a habitat. Some species permit all sorts of foreign 

 bodies, both animals and plants, to become attached to 

 their bodies, so that they are effectually concealed, and 



Fig. 80. — Arctic spider crab. 



even when moving, it seems as if a small forest of seaweed 

 were beiug transplanted to another locality. The largest 

 crustacean known belongs to the group of spider crabs. It 

 is the Macrocheira of Japan. Specimens of this spider 

 crab have been caught that measure from twelve to eigh- 

 teen feet between the tips of its outstretched claws, while 

 their bodies measure only about as many inches in width. 

 Fiddler crabs. — The fiddler crabs are abundant along the 

 seacoast, especially among salt marshes. They burrow in 

 the sand and have the habit of running sideways to and 



