CHAPTER II 



THE AMPHINEURA 



CLASS I AMPHINEURA, VON JHERING (1876) 

 ( = ISOPLEURA, Ray Lankester ; ACULIFERA, Hatschek). 



Order 1. Polyplacophora (Chitones). 

 Sub-Order 1. Eoplacophora. 



Family 1. Lepidopleuridae. 



Sub-Order 2. Mesoplacophora. 



Family 2. Ischnochitonidae. 

 3. Mopaliidae. 

 4. Acanthochitonidae. 

 5. Cryptoplacidae. 



Sub-Order 3. Teleoplacophora. 

 Family 6. Chitonidae. 



Order 2. Aplacophora. 



Sub-Order 1. Neomeniomorpha. 

 Family 1. Lepidomeniidae. 

 ,, 2. Neomeniidae. 

 ,, 3. Proneomeniidae. 

 4. Parameniidae. 



Sub-Order. 2. Chaetodermomorpha. 

 Family 5. Chaetodermatidae. 



Historical. The Chitones were formerly the only known forms of 

 this group, and for a long time they were placed in the Gastropoda, 

 near the genus Patella, the two forming the Order Cyclobranchia 

 of Cuvier. When Chaetoderma and Neomenia were investigated 

 from an anatomical point of view, von Jhering united them to the 

 Chitones (1876), and placed the two in a division of " Worms," 

 which he called Amphineura. But the molluscan nature of these 

 Amphineura is so clear, that they were reintroduced into the 



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