ZOOLOGY. 247 



21. Lerncsa. Arms ivio or three on each side, round, slen- 

 der ; caudal ovaries two. 



22. Scijllcca. Arms six^ in pairs, distant. 



****** Mouth before; body provided with peduncles or 



feet. 



23. Aphrodita. Body oval, furnished iTith eyes ; feelers 



two, setaceous, annulate. 



24. Amphitrite. Body annulate, issuing from a tube j teri' 

 taenia feathered ; eyes wanting. 



25. Spio. Body articulated, proceeding from a tube ; feel- 

 ers twoj long, simple ; eyes two. 



26. Nereis. Body long, creeping, with lateral pencilled 

 peduncles or feet • feelers simple. 



27. Nais. Body long, creeping ; peduncles or feet furnish- 

 ed with simple bristles; feelers wanting; eyes two, or 

 wanting. 



******* Mouth situated beneath, generally central. 



28. Physsophora. Body gelatinous, supported by an Air- 



bubble. 



39. Medusa. Sea-Nettle. Body gelatinous, smooth : 

 mouth beneath in the middle ; tentUQula placed below. 



R 4 



