THE CRUSTACEANS 109 
living crustacean, for the spread of the legs is fully 12 feet. It lives 
off the coast of Japan at depths greater than 600 feet, and is occa- 
sionally entangled in the set-lines of the fishermen. 
Our largest spider crabs are Libinia dubia, Fig. 77, and 

Fig. 77; Above: MALE SPIDER CRAB. 
Left: FEMALE SPIDER CRAB. 
Right: GHOST CRAB. 
Center: MUD CRAB. 
Libinia emarginata. They resemble each other closely, and the 
legs of both spread about eighteen inches, the males being larger, 
and having longer and stouter legs than the females. Libinia 
emarginata has more spines on its back than Labinia dubia. Both 
live from Cape Cod to the Gulf of Mexico, but Libinia emarginata 
extends north of Cape Cod to the coast of Maine, and lives usually 
in deeper water than Libinia dubia. Libinia dubia is very 
