130 CRUSTACEA. 



Nebalia (Leach). Carapace large, inclosing 



head, thorax, and part of abdomen ; antennae two 



pairs, large, branched; eyes two-stalked; feet 



twelve pairs, eight being branchial, and four 



natatory. 



N. bipes. Fig. 222 ; j. 



Order II. EDBIOPHTHALMA. 



Abdomen a rudimentary tubercle, 

 without distinct members. Branchial 

 vesicles suspended from the thorax. Lcemodipoda. 



Abdomen well-developed, and pro- 

 vided with five or six pairs of mem- 

 bers. 



Branchial vesicles almost always 

 absent from the thorax. First live 

 pairs of abdominal members almost of 

 the same form, unsuited to locomotion, 

 and apparently serving as gills . . . Isopoda. 



Branchial vesicles under thorax. 

 First five pairs of abdominal mem- 

 bers diversely formed, and serving for 

 locomotion Amphipoda. 



Sub- Order L LCEMODIPODA. 



Caprella (Lamk.). Body lengthened, slender, 

 cylindrical ; both pairs of antennas well developed ; 



