ARTHROPODA 239 
Order COPEPODA 
(Small size; body long, segmented; four to five pairs of once-branched appendages on 
thorax; abdomen without appendages; abundant in Fresh and 
salt water; many forms parasitic) 
Genera 
Cyclops 
Cetochilus 
Sapphirina 
Siphonostomata 
Nicothoé 
Order CIRRIPEDIA 
CImperfectly segmented; fixed or parasitic during adult life; inclosed in skin 
strengthened by calcareous plates; abdomen rudimentary; 
appendages biramous, usually six pairs) 
Species 
LL. anatifera 
Lepas L. striata 
L. pectinata 
B. balanoides 
B. eburneus 
Balanus B. rugosus 
B. geniculatus 
B. tintinnabulum 
RHIZOCEPHALA ; Sacculina (parasitic on crabs) 
(Parasitic) Peltogaster (parasitic on hermit-crabs) 
Suborders Genera 
Subclass 
Malacostraca 
(Highly organized Crustacea, usually of considerable size; appendages much differentiated) 
Order PHYLLOCARIDA 
(Small; covered with bivalved carapace; thoracic feet leaf-like; abdominal feet 
biramous; posterior segment terminates in two long spines; 
mostly fresh-water species) 
i Order SCHIZOPODA 
(Small; transparent; shrimp-like; thorax more or less completely covered with soft 
carapace; thoracic appendages biramous; eyes on stalks) 
Mysis M. sternolepis 
(Without gills or thoracic legs) 
Euphausia 
(With gills or thoracic legs) 
