2 5 8 



POLYCHAETA 



Branch A. Phanerocephala. 



Sub-Order 1. Nereidiformia[ = Errantia, auctt. + Ariciidae], 



Family 1. Syllidae 

 ,, 2. Hesionidae 

 3. Aphroditidae 



. see p. 306 

 308 



4. Phyllodocidae . 



5. Tomopteridae . 



6. Nereidae 



7. Nephthydidae 



309 

 313 

 315 

 315 

 317 



Sub-Order 2. 



Family 1. Spionidae . see p. 321 

 2. Polydoridae . 323 

 ,, 3. Chaetopteridae 323 



Family 8. Ampliinomidae see p. 318 

 9. Eunicidae . 318 

 10. Glyceridae . 320 

 ,, 11. Sphaerodoridae ,, 320 

 12. Ariciidae . 321 

 13. Typhloscolecidae 321 



Spioniformia. 



Family 4. Magelonidae . see p. 325 

 5. Ammocharidae 325 



Sub-Order 3. Terebelliformia. 



Family 1. Cirratulidae 

 2. Terebellidae 



see p. 325 Family 3. Ampharetidae see p. 330 

 327 4. Amphictenidae 330 



Sub-Order 4. Capitelliformia. 



Family. Capitellidae, see p. 331. 



Sub-Order 5. Scoleciformia. 



Family 4. Scalibregmidae see p. 334 

 5. Chlorhaemidae 334 

 6. Sternaspidae . 335 



Branch B. Cryptocephala. 

 Sub-Order 1. Sabelliformia. 



Family 1. Sabellidae . see p. 336 

 2. Eriographidae 338 



Family 3. Amphicorinidae see p. 339 

 4. Serpulidae , 339 



Sub-Order 2. Hermelliformia. 

 Family. Hermellidae, see p. 341. 



Comparative Anatomy of the Polychaeta. 



General Shape of the Body. The majority of the Poly- 

 chaeta have an elongated and very mobile body, like that of 

 Nereis, consisting of an indefinite and usually of a considerable 

 number of segments ; a few, however, have a shorter body, with 

 fewer segments, definite in number, for instance Aphrodite and 

 Polynoe, which have thirty to forty segments ; and some Hesio- 

 nids, with only some seventeen to twenty segments. 



