288 



TEE SEA SHORE 



yet, when occasion requires it, they will sometimes strike at the 

 object of their wrath with a most vigorous snap of their claws. 



In these crabs, too, we find most interesting instances of 

 protective resemblance to their surroundings. Some of the small, 

 slender-legged species are not to be recognised without a careful 

 search when they are at rest among clusters of sea firs, their thin 

 appendages and small bodies being hardly discernible in the midst 

 of the slender, encrusted branches, and their peculiar forms are still 



FIG. 215. SPIDER CRABS AT HOME 



more concealed by their colouring, which generally closely resembles 

 that of the growths among which they live. Further, the carapace 

 of spider crabs is in itself a garden on which thrive low forms 

 of both animal and vegetable life. Minute Alga, and occasionally 

 some of moderate size, are rooted to the shell, often securely held 

 by the aid of the rough hairs and tubercles that are so characteristic 

 of the exo-skeletons of these creatures ; and patches and tufts of 

 animal colonies that have found a convenient settlement on the 



