SECT. XV CLASSIFICATION OF CRUSTACEA 



255 



From the Trilobites, however, we are Inclined to 

 deduce at least a part of one important group of 

 modern Crustacea, the Ostracoda. We think it 



Ostracoda Cirripedia Copepoda Apiis Phyllopoda Malacostra 



Proposed genealogj' of the Crustacea. It w ill be seen from the text that though we 

 have here given only one root for the Ostracoda it is probable that they have 

 had at least a twofold origin. 



probable that the Crustaceans in question ma}- be 

 deduced both from Trilobites and Phyllopods. The 

 strong likeness between these early forms, especially in 

 their larval stages, now perpetuated in the Ostracoda, 



