METAMORPHOSIS 



place ; at this stage the body has the appearance shown in 

 Fig. 51. The region of the head at the base of the antennae 

 now becomes greatly swollen and elongated to form the peduncle 



Fii;. 40. Nauplius larva of Lepa.s fascicularis, x 12. A v A, 1st and 2nd antennae ; 

 />', brain ; E, eye ; //, frouto-lateral horn ; J/, mandible ; S, stomach. (After 

 Groom.) 



or stalk of the adult ; the larval bivalve carapace is cast off 

 and on the external surface of the mantle the calcifications begin 

 which will give rise to the exoskeletal plates of the adult. This 

 r-'iiiun is known as the " capitulum " of the adult, as opposed to the 

 " peduncle." The young Cirripede is now known as a pupa, and 

 from this stage the adult form is reached by a gradual transition. 



VOL. IV G 



