76 HOUSE, GARDEN, AND FIELD 



a " sea-louse," and thinks it may have been the food of 

 the barnacle. 



We have not yet sufficiently described the Cypris-larva 

 of the barnacle, and we must by no means pass over the 

 transformation by which it is converted into a fixed 

 barnacle. The Cypris-larva is furnished with a pair of 

 new antennae, which shortly before, that is, in the late 

 Nauplius, were to be seen telescoped into the fore part of 

 the body, like the growing antennae in an insect-larva 

 shortly before pupation. It has three more pairs of legs 

 than the Nauplius, bringing the number up to six. The 

 bivalve shell is large enough to enclose the whole body, 

 including the antennae, and can be closed by an adductor 

 muscle, except at the ends, which always gape a little. 

 The Cypris-larva swims rapidly, or creeps by the help of 

 its prehensile antennae. The lowest joint but one of the 

 antenna is furnished with a sucker, which adheres even 

 to so smooth a surface as that of glass. The mouth of the 

 Cypris is closed, and no food can be taken in during this 

 stage. 



When the Cypris, swimming or creeping through the 

 water, and guided by its eyes and antennae, has discovered 

 a spot convenient for its settlement, it applies its suckers 

 and immediately adheres. A sticky fluid is poured out 

 from the suckers at this moment or even earlier, for free 

 larvae have been found with their suckers already charged 

 with cement. The body is now parallel to the surface of 

 attachment, in the position of a shrimp resting on the 

 ground. The skin splits along the mid-dorsal line, and 

 the bivalve shell, together with the compound eyes and 

 other parts which will henceforth be superfluous, are shed. 

 Then the young barnacle bends its body into the position 

 which it will hereafter retain. When it first became 

 attached, the limbs rested upon the ground, but the body 

 now erects itself until the animal stands upon its head. 

 Just after erection the young rock-barnacle is very like a 

 stalked barnacle in the same stage, and consists of an 



