DEC A POD A . I'ORCELLA NA D.E. 



ANOMOUHA. 



GENUS PORCELLANA, Lam. 



Cancer. Lin. Herbst. Pennant. 



PoRCELLANA. Lanmrck, Edwards. 



PoRCELLANA PisiDiA. Lcach, Desmarest. 



Generic Character. — External antennce inserted at the outer 

 side of the eyes ; the basal portion formed of three joints, of which 

 the second is the largest and the longest ; the terminal portion very 

 long, setaceous. Internal antenna; concealed beneath the front, 

 very small. External jyedipalps greatly developed ; the second 

 joint very large, rounded, with a single tooth on the outer anterior 

 angle ; the third joint much smaller, irregularly trigonal, and with 

 the remaining joints fringed with long hair at the edges. Anterior 

 feet very large, and more or less flattened ; the arm very short ; 

 the wrist long and dilated on the upper and inner edge, so as to 

 form a hollow space, in which the liand lies when retracted ; the 

 hand narrow at its base, becoming very broad forwards ; the 

 fingers strong and scarcely toothed. Second, third, and fourtli 

 pairs of feet ambulatory, nearly cylindrical ; fifth pair very small, 

 didactyle, and doubled together at the latero-posterior angle of the 

 curaiiace. Carapace suborbicular, depressed. Ei/es small, lodged 

 in an orhit, the parieties of which are imperfect, excepting above. 

 Abdomen very large, much developed, nearly as long as tlie cara- 

 pace, ordinarily closed against the sternum, composed uf seven 

 distinct segments, and terminating in a broad fan-like tail, formed, 

 as in the Macroura, of the terminal segment of the abdomen and 

 the appendices of the penultimate. 



In this genus we find a marked approach to the Ma- 

 crourous group in the development of the podipalps and 

 of the tail, as well as in several other less obvious charac- 



