354 AETICULATA: CRUSTACEA. 



The Crustacea have been variously divided, some nat- 

 uralists recognizing few orders, others many.* 



Professor Verrill, the eminent Zoologist of Yale Col- 

 lege, has adopted the following classification of the 

 Crustacea. It is a modification of that of G. O. Sars 

 (Fresh-water Crustacea of Norway) : 



I. SUB-CLASS, MALACOSTRACA. 



ORDER I. THORACOSTRACA = PODOPHTHALMIA (nearly). 



Sub-order I. DECAPODA (including Brachyura, Auomoura, 



Macrura, and Schizopoda (Mysis). 

 " II. STOMAPODA or Squilloidea. 

 " " III. CUMACEA (Diastylis). 



ORDER II. ARTHROSTRACA = TETRADECAPODA. 



Sub-order I. AMPIIIPODA. 

 " " II. ISOPODA. 



II. SUB-CLASS, ENTOMOSTRACA. 



ORDER III. LIMULOIDEA. 



IV. TRILOBITA. 

 " V. PHYLLOPODA. 

 VI. CLADOCERA. 



VII. COPEPODA (including Lerncea,Caligus, Argu- 

 lus, etc.). 



" VIII. OSTRACODA. 

 " IX. ClRRIPEDIA. 



* Excluding the Cirripedia, Milne-Edwards recognizes the following 

 Orders of the Crustacea : 



1. Decapoda, including Brachyura, Anomoura, Macroura. 



2. Stomapoda, as Mysis, Squilla, etc. 



3. Arnphipoda, as Gammarus, Talitra, etc. 



4. Lasmodipoda, as Caprella, Cyamus, etc. 



5. Isopodu, as Idotea, etc. 



6. Phyllopoda, as Branchipus, Limuaclia, Nebalia, etc. 



7. Cladocera, as Daphnia, etc. 



