CONTENTS. Xlll 



CHAPTER XIX. CRUSTACEA-co/itinwed. PAGE 



H. Glands (antennal and shell-glands) . . .178 



/. Genital organs . . . . 180 



Literature referring to the embryonic development of the Crustacea 181 



II. Metamorphosis of the Crustacea . . . . 190 



1. The Nauplius stage . . . . 190 



Primary segmentation of the Nauplius . . . 191 



Metanauplius . . . . . 192 



Phylogenetic significance of the Nauplius . . .192 



Further development of the Nauplius stage . . . 193 



2. Typical form of the Crustacean limbs . ... 193 



Significance of the Phyllopodan limbs . . . 195 



3. Metamorphosis of the Phyllopoda . ... 196 



A. Branchiopoda . . . . 196 



Apus . . . ... 196 



Branchipus . . . . 199 



Estheria . . . . . 201 



General considerations regarding the Branchiopoda . 202 



B. Cladocera . . . ... 203 



4. Metamorphosis of the Ostracoda . ... 205 



Cypridae . . . ... 205 



Cytheridae, Cypridinidae . . ... 208 



Halocypridae . . . ... 209 



5. Metamorphosis of the Cirripedia . ... 209 



A. Thoracica . . . ... 209 



Nauplius . . ... 209 



Metanauplius . . . . 213 



Free-swimming Cypris stage . . . 214 



Attachment and transformation of the Cypris larva . 216 

 Development of the adult Cirri pede shell . .219 



Metamorphosis of the Balanidae . . .219 



B. Abdominalia . . ... 220 



C. Rhizocephala . . . . 221 



Nauplius of Sacculina . . . 221 



Cypris stage of Sacculina . ... 221 



Kentrogon stage . . ... 223 



Sacculina interna . . ... 226 



Sacculina externa . . . . . 228 



D. Ascothoracida . . ... 228 



E. The morphological derivation of the complemental males 229 



6. Metamorphosis of the Copepoda . ... 231 



General considerations . . ... 231 



A. Gnathostomata . . ... 232 



Character of the Nauplius stage . . 233 



Metanauplius . . ... 234 



Cyclops stage . . ... 235 



B. Parasita . . . ... 237 



General considerations regarding parasitic Copepoda. 237 



Chondracanthidae . . ... 239 



Philichthyidae . . ... 239 



Dichelestiidae . . 239 



