LIST OF ILLUSTRATIONS xxvii 



FIG. PAGE 



371. Polynoe setosissima . . 457 



372. Galeolaria ccespitosa 457 



373. Chfetopterus . . 458 



374. Setae of various Polychseta . 458 



375. Section of setigerous sac of an Oligochsete 458 



376. Polynoe extenuata, anterior end . 459 



377. Polychaeta, various, heads . . 460 



378. Tu ifex ... .461 



379. Terebella . . 462 



380. Aphrodite, enteric canal . 464 



381. Saccocirrus, transverse section 466 



382. Phyllodoce, nephridium . 468 



383. Nephridia and ccelomoducts . . 469 



384. Diagram illustrating development -of gonad of Polychoeta . 470 



385. Pionosyllis elegans . . 472 



386. Spirorbis Isevis . 473 



387. Eupomatus, development of trochophore . . 474 



388. Autolytus cormitus, budding 475 



389. Syllis ramosa . . . 476 



390. Serpulae with their tubes . 476 



391. Myzostoma . . . 478 



392. ,, anatomy . 479 



393. Echiurus ... .480 



394. ,, anatomy ... 481 



395. ,, nervous system . .481 



396. Bonellia viridis, female . . 482 



397. Bonellia, anatomy . . 482 



398. Echiurus, ciliated funnel 482 



399. Bonellia, male . . 483 



400. Echiurus, trochophore 



401. Sipunculus nuclus, anterior extremity . 485 



402. ,, tentacular fold . . 485 



403. anatomy . 486 



404. ,, ,, nervous system . 486 



405. Priapulus ... 490 



406. Polygordius neapolitanus 



407. Protodrilus . . 492 



408. Polygordius neapolitanus, transverse section . 492 



409. trochophore . 493 



410. ,, later stage . . 493 



411. Hirudo medicinalis .... . 495 



412. ,, ,, transverse section . . 496 



413. .. jaw . . 497 



414. ,, australis, dissection from dorsal aspect . 498 



415. ., australis left side . . 499 



416. ,, medicinalis, nephridium . . . . 500 



417. ,, diagram of blood-channels 501 



418. ,, section of eye ........ 502 



