i 7 S 



CIRRIPEDS. 



panded, it will be seen that their plumose and flexible stems form 

 a most wonderful prehensile apparatus, admirably adapted to 

 entangle any nutritious particles of minute living creatures that 

 may happen to be present in the circumscribed space over which 

 this singular casting-net is thrown, and drag them down into the 

 vicinity of the mouth, where, being seized by the jaws, they are 

 crushed and appropriated as food. No sense but that of touch 

 is required for the success of this singular mode of fishing, and 

 the delicacy with which the arms perceive the slighest contact of 

 foreign bodies shows that they are eminently sensitive. 



FIG. 179. CIRRI OF BARNACLE. 



FIG. iSo. YOUNG OF BARNACLE. 



It is from these remarkably-constructed limbs or cirri that 

 the Order derives its name. Although in their adult state the 

 Cirripeds are fixed and stationary, and enclosed in dense and 

 strong shells, the newly-hatched young present a very different 

 shape, and, strange to say, are furnished with limbs calculated 

 to enable them to swim freely about, under the appearance of 

 Entomostracous Crustaceans; and it is only after undergoing 

 several changes of form, that they lose their wandering . habits! 

 The young Cirripeds, on emerging from the eggs, are very different 

 in structure from their parents. They possess locomotive organs 

 consisting of a large pair of limbs provided with a sucker and 

 hooks, adapted for mooring themselves at pleasure to any foreign 

 object; and also of six pairs of swimming-legs, that act in concert 

 like oars. Besides these they have a tail bent under their body, 



