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. 
2? 
9 
Sub-Order 3. Teleoplacophora. 
Family 6. Chitonidae. 
Order 2. Aplacophora. 
Sub-Order 1. Neomeniomorpha. 
Family 1. Lepidomeniidae. 
2. Neomeniidae. 
3. Proneomeniidae. 
4. Parameniidae. 
99 
39 
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 
40 
