BARNACLES. 
angles from the surfaco. Now the “fingers,” expanded 
like a fan, and curved like a half-open hand, make the 
framework of a net, while the transverse bristles, those 
of each “ finger ” meeting and interlocking with those of 
the next, constitute a series of meshes occupying the inter- 
stices, and the whole, cast out and withdrawn, form a most 
efficient strainer of the water, arresting every minute 
atom, living or dead, which, being then passed down to 
the mouth at the bottom of the net, is either swallowed 
or rejected, according as it is fit for food or worthless. 
The Barnacle, whether sessile or stalked, passes through 
a series of metamorphoses, which shew that, although its 
appearance and instincts when adult have a great resem- 
blance to those of the Mollosca, its affinities are truly 
with the Crustacea. It begins life in a form exactly like 
that of a young Entomostracous Crustacean, with abroad 
carapace, a single eye, two pairs of antemue, three pairs 
of jointed, branched, and well-bristled legs, and a forked 
tail. It casts off its skill twice, undergoing, especially 
at the second moult, a considerable change of figure. At 
the third moult it has assumed almost the form of a 
Cypris or Cythere, being enclosed in a bivalve shell, in which 
the front of the head, with the antennae, is greatly de- 
veloped, equalling in bulk all the rest of the body. The 
single eye has become two, which are very large, and 
attached to the outer arms of two bent processes like the 
letters U U, which are seen within the thorax. 
In this stage the little animal searches about for some 
suitable spot for permanent residence ; a ship’s bottom, a 
piece of floating timber, the back of a whale or turtle, or 
the solid rock. When its selection is made, the two antenme, 
r 
