108 SEA-SHORE LIFE 
The Orchid Crab, (Gecarcinus lateralis, Fig. 76), is a land crab, 
and literally swarms over many of the Florida Keys and West In- 
dies. It is also found at the Bermudas, and on the coast of South 
America. The shell is about two inches wide and a little less than 
this in length, with smooth, rounded edges. The central parts of 
the back are dark purple—almost black, while the sides of the shell 
and the large claws are rose-red. ‘The walking legs and under parts 
are dull yellow. This crab spends almost its entire life upon land, 
the gills being small and enclosed in large chambers wl ich admit 
air but maintain the cavity moist. The creature lives under damp 
logs or leaves, or digs burrows fully three feet in depth; and is 
often found fully twenty feet above high tide level. 
It is mainly nocturnal, and great numbers of them crawl about 
during the night seeking all manner of refuse and carrion upon 
which they feed. In the spring they all visit the ocean to breed, 
and in midsummer they retire to the depths of their burrows to 
moult. The crab is a fairly rapid runner and an excellent climber. 
It is also a pugnacious fighter, being well protected by its very 
hard shell. 
The Spider Crabs, (lig. 77). These are sluggish, weak-clawed 
crabs with remarkably long, slender legs. Their bodies are usually 
flask-shaped with long, tapering snout, and short eye-stalks. 
Although apparently stupid, these crabs have what is probably the 
most highly developed nervous system found in the crustacea, for 
the gangha of the body are often united into a single disk-like brain. 
Many of the spider crabs have the habit of placing bits of sea- 
weed, hydroids and other marine growths upon their backs, so that 
the crab is completely hidden under a veritable marine garden. It 
has been found that the crab deliberately bites off fragments of 
weeds, chews them for a time and places the weeds upon its own 
back, where they are caught by the saw-edged or hooked-hairs of 
the crab’s back, and probably also anchored by means of adhesive 
mucous from the crab’s mouth. The crab always covers itself with 
the sort of weeds, etc., found in its immediate vicinity, and if 
removed to another situation, the appearance of which is different, 
promptly removes the old weeds and replaces them with those which 
match the new surroundings. 
One of the spider crabs ( Maerocheira kampferr) is the largest 
