LIST OF ILLUSTRATIONS xxvii 



FIG. PAGE 



366. Vermilia ccespitosa 468 



367. Chietopterus 469 



368. Setee of various Polychreta 470 



369. Section of setigerous sac of an Oligochtete 470 



370. Polynoe extenuata, anterior end 471 



371. Polychreta, various, heads 472 



372. Tubifex .473 



373. Terebella 474 



374. Aphrodita, enteric canal 475 



375. Saccocirrus, transverse section 477 



376. Phyllodoce, nephridium 479 



377. Nephridia and coelomoducts 480 



378. Diagram illustrating development of gonad of Polychreta . . 482 



379. Spirorbis lams . 484 



380. Eupomatus, development of trochophore 485 



381. Autolytus cornutus, budding 487 



382. Syllis ramosa 487 



383. Serpulre with their tubes 488 



384. Myzostomum 490 



385. ,, anatomy 491 



386. Sipunculus nudus, anterior extremity 492 



387. ,, ,, tentacular fold 493 



388. ,, ,, anatomy 494 



389. ,, ,, nervous system 494 



390. Bonellia viridis, female 497 



391. Echiurus 497 



392. Priapulus 498 



393. Bonellia, anatomy ... 499 



394. Echiurus, ciliated funnel 499 



395. ,, anatomy 500 



396. ,, nervous system 500 



397. Bonellia, male 501 



398. Echiurus, trochophore 501 



399. Polygordius neapolitanus 503 



400. Protodrilus 504 



401. Polygordius neapolitanus, transverse section 504 



402. ,, ,, trochophore 505 



403. ,, ,, ,, later stage .... 505 



404. Hirudo medicinalis . . 507 



405. ,, ,, transverse section 508 



406. ,, jaw 509 



407. ,, australis, dissection from dorsal aspect . . . 510 



408. ,, australis, ,, ,, left side . . . . .511 



409. ,, medicinalis, nephridium 512 



410. ,, diagram of blood-channels 513 



411. ,, section of eye 514 



412. ,, cocoon 515 



413. Three Rhynchobdellicla . . 517 



