!58 



THE UNIVERSE. 



bands on the mountains and in the forests of Brazil, where 

 they dwell in holes. But each year these animals make a 

 l^ilgrimage to the sea in order to deposit their young there, 

 and this act performed they return to their favourite haunts. 



As it is necessary during this long and double journey 

 to breathe either Avater or at least moist air, natm-e has 

 provided for every emergency. The tourlourous, for these 

 crabs are popularly known by that name, possess for this 

 purpose, ab(^ve the branchite, a kind of sacks which are just 

 reservoirs of liquid. When one of these crustaceans wants 

 to travel, its first step is to take in a stock of water by 

 completely filling these sacks. During its march the 

 liquid falls droji by drop upon the resjjiratory organs, and 

 moistens the vessels. The branchife being thus constantly 

 wetted, the aquatic animal can live in air and move about, 

 in spite of the dryness and heat. Like a locomotive in 

 action, it carries with it its supply of water, and has only 

 to feed itself 



A singular fish, the anabas (Percn scandens), displays 

 an organization exactly analogous to that of the crab we 



1*7. Water-reservoir of the Anabas. 



liavejust spoken of. It fills with water a lab3Tinthiform 

 cavity which is also situated above its branchia\ Then. 

 after having taken tliis precaution, tlio prudent fish lioldly 



