Crustacea. 7653 



soft, rests for some time, as if exhausted, near the cast-off skeleton ; 

 however, should there be any cause, it is capable of swimming away 

 immediately. 



The new creature is a perfect representation of the old one slightly 

 enlarged ; every hair is produced complete. This is capable of 

 demonstration before moulting, for we have repeatedly observed the 

 new hairs attached to the new skin while examining specimens under 

 the microscope, where the second layer of similarly furnished integu- 

 ments is distinctly visible; and it has always appeared to be a curious 

 fact, and contrary to anticipation, that the new materials (hairs, 

 spines, &c.) are not developed within each corresponding hair, spine, 

 tooth, &c., they being visible as a second and independent armature. 



The crevices among rocks and the shelter afforded by overhanging 

 stones are the abodes of most of the larger crabs and lobsters, par- 

 ticularly those which dwell upon the shores. Great activity most 

 of them possess, and will often, when the rocks are slippery, give 

 much trouble and perhaps more than a single fall before you can 

 secure one. Professor Kinahan states that in the Chinca Islands, 

 " Running over shingle, foraging among the dead sea-lions and other 

 . animal and vegetable remains, climbing in immense numbers "over 

 the perpendicular faces of the cliffs above, the wrinkled beach-crabs 

 [Grapsiis strigosus), most striking from their gaudy colours, size and 

 swiftness, cannot fail to arrest the attention of even an unscientific 

 observer; the chase after them, especially on the summits of the cliffs, 

 is exciting, being fraught with danger through the slipperiness of the 

 footliold. It was most laughable to see the way in which they would 

 at times, after escaping capture, behind some inaccessible projecting 

 point, peep round a corner at you, as though exulting in having 

 eluded your pursuit. They may be often seen, too, in fierce combat 

 on the rocks, but seemingly as careful as any delicate young lady 

 of wetting their feet." 



The abode of others appear to be chosen from a more decided 

 advantage which is instinctively known to the animal. The pearly 

 raspberry crab {Porcellana perlata), Professor,Kinahan tells us, chooses 

 the empty shell of the fixed Balani to coil itself in ; and we know 

 that some, without being parasitic in the correct meaning of the word, 

 attach themselves to fish or pieces of wood, and swim the ocean by 

 their assistance. These latter have the last pair of legs so arranged as 

 to have the appearance of being placed upon their backs, distorted 

 from their normal position by the continual practice, from generation 

 to generation, of straining the limbs to grasp at things almost beyond 



