SECT. virr. C1RRIPEDIA. 217 



the protrusion of a pair of prehensile limbs; and six pairs 

 of swimming feet cause the animal to swim by a succes- 

 sion of bounds. Instead of the single eye, it has now 

 two raised on pedestals, attached to the anterior part of 

 the body. 



This animal having selected a piece of floating wood 

 for its permanent abode, attaches itself to it by the 

 head, which is immovably fixed by a tenacious glue ex- 

 uded from glands at the base of the antennae. The 

 bivalve shell is subsequently thrown off, a portion of the 

 head becomes excessively elongated to form the peduncle 

 of the Barnacle or Lepas, and in that state it is exactly 



Fig. 157. Lepas. 



like the Lucifer Stomapod. In the Balanus, on the con- 

 trary, the head expands into a broad disk of adhesion, 

 and the animal resembles the Mysis or Opossum Shrimp. 



From the first segment of the throat a prolongation is 

 sent backwards which covers the whole body, and the 

 outer layer is converted into the multivalve shell ; and 

 the three pairs of cirrhated feet, which were formed in 

 the larval state, now bend backwards from the other three 

 rings of the throat. 



Though the Cirripeds lose their eyes in their mature 

 state, they are sensitive to light. They draw in their 

 cirrhated feet, and the Balanus even closes the lid of its 

 shell under the shadow of a passing cloud. 



