CRABS. 251 
tion. The black mud along the coast of Borneo assumes quite 
a brilliant blue tinge, when, at low water, during the heat of 
the day, the ccrulean Gelasimi 
come forth to feed. 
The Venetian lagoons also har- 
bour a vast number of the common 
Shore-Crab (Portunus Meenas), 
the catching of which affords a i 
profitable employment to the in- Calling-Crab of Ceyion. 
habitants of those swampy regions. 
Whole cargoes are sent to Istria, where they are used as bait for 
anchovies. The fishermen gather them a short time before they 
cast their shell, and preserve them in baskets, until the moulting 
process has been effected, when they are reckoned a delicacy even 
on the best tables. On attempting to seize this crab, it runs 
rapidly sideways, and conceals itself in the mud; but when un- 
successful, it raises itself with a menacing mien, beats its claws 
noisily together, as if in defiance of the enemy, and prepares for 
a valiant defence, like a true knight. 
The most valuable short-tailed crustacean of the North Sea is 
undoubtedly the Great Crab (Cancer pagurus), which attains 
a weight of from four to five pounds, and is consumed by 
thousands in the summer, when it is in season and heaviest. 
It is«caught in wicker-baskets, arranged so as to permit an easy 
entrance, while egress is not to be thought of. 
The legs of the crabs are very differently formed in various 
species. In those which have been called sea-spiders they are 
very long, thin, and weak, so that the animal swims badly, and is 
a slow and uncertain pedestrian, For greater security it therefore 
generally seeks a greater depth, where, concealed among the sea~ 
weeds, it wages war with annelides, planarias, and small mollusks 
Sea-spiders are often found on the oyster-banks, and considered 
injurious by the fishermen, who unmercifully destroy them 
whenever they get hold of them. 
In other species the legs are short, muscular, and powerful, 
so as rapidly to carry along the comparatively light body. The 
tropical land-crabs and the genera Ocypoda and Grapsus, which 
form the link between the former and the real sea-crabs, are 
particularly distinguished in this respect. 
The Rider or Racer (Ocypoda cursor), who is found on the 
