DECAPOD A PAGURtDM. 



ANOMOURA. 



GENUS PAGURUS. FABR. 



CANCER, Linn. Herbst. 



ASTACUS, Pennant, Degeer. 



PAGURUS, Fabr. Bosc. Lam. Latr. Leach, Edwards. 



Generic character. External antennae inserted in the same 

 line with the peduncles of the eyes, and furnished with a large 

 moveable spine, which represents the palpus of this organ ; the last 

 joint of the peduncle long, slender, and cylindrical ; filament com- 

 posed of many articulations, very long and setaceous. Internal 

 antenna?, placed immediately above the ocular peduncles ; the first 

 joint nearly globular ; the second and third elongate and slender, 

 the terminal portion consisting of two setce, the superior com- 

 pressed, hairy ; the inferior shorter, filiform. External pedipalps 

 pediform, having five exserted joints ; the palpus much developed, 

 nearly as long as the stalk. Anterior feet very unequal, one of the 

 hands being large and tumid ; the second and third pairs long, 

 ambulatory, with long curved nails; the fourth and fifth pairs 

 small, rudimentary, sub-didactyle, the latter more distinctly so than 

 the former. Cephalo-tkorax membranaceous, shorter than the ab- 

 dominal portion of the body. Carapace covering only the anterior 

 and inferior portion of the thorax. Abdomen greatly developed, 

 elongated, membranous, furnished on the upper surface with rudi- 

 mentary crustaceous plates. Tail crustaceous, of three joints, 

 the second joint with appendices on each side. 



The family PAGURID^E, and particularly the present genus, 

 is composed of some of the most curious and anomalous 

 forms in the whole of the class. Whilst the Birgus, leaving 

 the water, and even disdaining to crawl on the ground like 

 the true land-crab, climbs the height of the cocoa-tree, and 



