36 CRUSTACEA. 



whose shells they are found, on friendly terms, warning them of 

 danger and seeking food for them. The inhabitants of certain dis- 

 tricts, at the present day, attribute to their presence the unwhole- 

 some qualities sometimes manifested in the Mytili(l). 



We now arrive at Crustacea, which, although analogous to those 

 just mentioned in the insertion of their ocular pedicles, are re- 

 moved from them in respect to their shell. It is heart-shaped and 

 truncated posteriorly, elevated, dilated and rounded on the sides 

 near the anterior angles. The ocular pedicles are shorter than those 

 of the preceding subgenera, and do not quite extend to the lateral 

 extremities of the shell. The intermediate antennae are always ter- 

 minated by two very distinct divisions. The inhabitants of the 

 f>onch colonies designate them by various appellations, such as, 

 Tourlouroux, Crabes-pcints^ Crates de terre, and Crabes violets, which 

 may apply to different species, or to varieties from age; no observa- 

 tions worthy of credence have as yet settled this point of nomencla- 

 ture. These animals more particularly inhabit intertropical coun- 

 tries and those which adjoin them. Their habits are a constant 

 source of interest to travellers, but by abstracting from their ac- 

 counts all improbable and doubtful facts, their history will be as 

 follows. The greater portion of their life is passed on land, where 

 they secrete themselves in holes, from which they never issue but at 

 night. Some inhabit cemeteries. Once in the year, about the spawn- 

 ing season, they collect in immense bands and pursue a direct course 

 to the sea, heedless of all obstacles; after depositing their ova, they 

 return much enfeebled. It is said that they seal up the mouth of 

 their burrow during the time they are casting their shell. When 

 this is effected, and while yet soft, they are called Boursiers, and 

 their flesh is much esteemed, although sometimes poisonous. This 

 quality is attributed to the fruit of the manchineel, which they are 

 supposed, falsely perhaps, to have eaten. In some of them, such 

 as the 



UcA, Lat., 



The size of the feet, commencing, with those of the second pair, 

 progressively diminishes; they are extremely pilose, and the tarsi 

 simply sulcated without any remarkable spines or dentations. 



The only species known — Cancer uca, L., Herbst., VI, 38, 

 inhabits the marshes of Guiana and of Brazil. 

 In others, the third and fourth pair of feet are longer than the 



(1) For species see Leach, Make. Podoph. Britt, and Desmar., Consider. 

 Gen^r. sur les Crust., 116. 



