THE COMMON SHORE CRAB. 



199 



number annually taken is immense, and as the occupation of procuring them is principally carried on 

 by persons who are past the more laborious and dangerous pursuits of general fishing, it affords a means 

 of subsistence to many a poor man who, from age or infirmity, would be unable without it to keep 

 himself and his family from the workhouse. They are taken in what are termed ' ; crab-pots," a sort of 

 wicker trap, made by preference of the twigs of the golden willow (Salix vitellina), at least, in many 

 parts of the coast, on account, as the fisher-folk say, of its great durability and toughness. These pots 

 are formed on the principle of a common wire mouse-trap, but with the entrance at the top. They 

 are baited with pieces of fish, generally of some otherwise useless kind ; these are fixed into the pots 

 by means of a skewer. The pots are sunk by stones attached to the bottom ; and the situation where 

 they are dropped is indicated, and the means of raising them provided, by a long line fixed to the 

 creel, or pot, having a piece of cork attached to its free end. These pieces float the line, and at 

 the same time serve to designate the owners of the 

 different pots, one perhaps having three corks 

 near together, towards the extremity of the line, 

 and two distant ones; another may have one 

 cork fastened crosswise ; another two fastened 

 together, and so on. 



The Common Shore Crab (Fig. 14, Carci- 

 nus mamas), so abundant in very shallow 

 water around the coasts, and so industrious a 

 scavenger between tide-marks, spends really much 

 of its time almost out of water or on the edge 

 of the advancing and the skirts of the receding 

 tide. It is a true running Crab, yet its relations 

 are all swimming Crabs, having their hind pair 

 of feet specially modified for swimming, which 

 is- not the case in Carcinus. The front margin 

 of the carapace is strongly toothed with five teeth 

 on each side, and three lobes in front ; the eyes 

 are larger and certainly more useful " optics " than 

 those of the great Crab. To any one who is a lover 

 of an aquarium this very common Crab is an excellent and amusing species to keep and tame, for 

 it soon loses all idea of shyness, and will " come to be fed " like any other pet, and take its food 

 sharply. When very young these Shore Crabs moult frequently, and, being easily kept in small 

 vessels of sea-water, one can all the more readily study their habits. One which was thus kept in 

 confinement moulted on llth April, 22nd May, the 3rd July, the 30th August, and 26th 

 September of the same year, the acceleration of the last moult being attributed to the creature 

 having been fed " like a prize beast," on purpose to try the effect on its growth. In casting its 

 shell a Crab not only parts with every joint and plate of its many-jointed body, antenna;, 

 foot-jaws, claws, and tail, but the very lining of its gills, of its stomach, of its eyes, and of 

 other parts, is thrown off, and thus, when the creature has escaped, the shell seems as perfect 

 nearly as the animal itself. 



Pennant's Swimming Crab (Portunus variegatus) has a carapace which is rather longer than 

 wide, and is toothed at its front border. Its fore legs are short, with exceedingly sharp claws 

 (chelae). The last pair of legs are flat and spatulate, and like an oar-blade, well adapted for 

 swimming ; the other three pairs of simple legs are fitted for running. They are common on the 

 shores of the Firth of Forth and the Moray Firth, and in Ireland. Its colour is a dull purple-white 

 mottled with a darker hue. 



The Velvet Fiddler Crab (Portunus puber) has its front border armed with at least ten spines, 

 and its entire carapace densely covered with hairs. The chelae, or claws, and also the four pairs of 

 simple legs, are thickly coated with a dense pile of fur. All the limbs have raised longitudinal lines 

 or ridges upon their joints. The general colour of the Velvet Fiddler Crab is brown, but the longi- 

 tudinal ridges on the legs are blue. This Crab is not uncommon on the south-west coast of England 



Fig. 13. MAIA SQUINADO. 



