208 MANUAL OF ZOOLOGY. 



Sub-class III. Entomostraca. 



Order 6. Ostracoda. \ t ■ -t \. a 



„ n.Copepoda. |Z.^^^«,Lophyropoda. 



„ 8. Cladocera. \ 



„ 9. Phyllopoda. \ Legion, Branchiopoda. 



„ 10. Trilobita. ) 



„ II. Merostomata. 



Sub-class IV. Malacostraca. 



Division a. Edriophthalmata. 



Order 12. Lxmodipoda. 

 „ 13. Isopoda. 

 „ 14. Amphipoda. 



Division b. Podophthalmata. 



Order 15. Stomapoda. 

 „ 16. Decapoda. 



Tribe a. Macrura. 

 „ b. Anomura. ■ 

 „ c. Brachyura. 



• CHAPTER XXXII. 



EPIZOA AND CIRRIPEDIA. 



Sub-class I. Epizoa {Haustdlata). — The members of this sub- 

 class of the Crustacea are in the adult state parasitic upon the 

 bodies of fishes, and are usually deformed ; but in the young 

 condition they are locojnotive, and are furnished with antennae 

 and eyes. The mouth is suctorial, and the limbs are terminated 

 l)y suckers, hooks, or bristles. There are no differentiated 

 respiratory organs, but respiration is , performed by the surface 

 of the body. The males are rudimentary, and are much smaller 

 than the females, which are usually furnished with externa! 

 ovisacs. The Epizoa are closely allied to the Copepoda, and 

 may, indeed, be regarded as parasitic Copepods, having the 

 mouth modified so as to form a suctorial tube or beak, result- 

 ing from the elongation of the labrum and labium. Within 

 this are almost always two stylets or lancet-shaped mandibles, 

 used in piercing. The feet are often deformed by age, or 



