152 THE ANNELIDES. §$ 142. 
Genera: Tetrastemma, Polystemma, Micrura, Notospermus, Meckelia, 
Polia, Nemertes, Borlasia. 
SUB-ORDER II. HIRUDINEI. 
Posterior extremity of body provided with a sucker. 
Genera: Branchiobdella, Prscicola, Clepsine, Nephelis, Haemopis, Aulaco. 
stomum, Sanguisuga, Pontobdella. 
ORDER Il. CHAETOPODES. 
Body provided with bristles. — 
SUB-ORDER III. LUMBRICINI (ABRANCHIATI.) 
Body without feet. 
Genera: Chaetogaster, Enchytraeus, Nais, Lumbriculus, Euaxes, Saenu- 
ris, Lumbricus, Sternaspis. 
SUB-ORDER IV. CAPITIBRANCHIATI. 
Body provided with feet; branchiae situated upon the cephalic ex- 
tremity. 
Genera: Siphonostomum, Chloraema, Amphicora, Serpula, Sabella, Am- 
phitrite, Terebella. 
SUB-ORDER V. DORSIBRANCHIATI. 
Body provided with feet; branchiae situated upon its segments. 
Genera: Arenicola, Ammotrypane, Chaetopterus, Aricia, Aricinella, Cir- 
ratulus, Peripatus, Glycera, Goniada, Nephtys, Alciopa, Syillis, Phyllo- 
doce, Hesione, Lycastis, Nereis, Oenone, Aglaura, Lumbrinereis, Eunice, 
Amphinome, Sigalion, Polynoé, Aphrodite. 
BIBLIOGRAPHY. 
Pallas. Miscellanea zoologica. Hague, 1766, p. 72. 
O. F. Miller. Von den Wirmen des stissen und salzigen Wassers. 
Copenhagen, 1771. 
Savigny. Description de Egypte. Histoire Naturelle. Tom, XXT. 
1826. Annelides, Also, Isis, 1832, p. 937. 
a ae Monographie de la famille des Hirudinées, 
Morren. De lumbrici terrestris historia naturali, nec non Anatomia. 
Bruxelles, 1829. 
Paris, 
