xxiv LIST OF ILLUSTRATIONS 



FH;. PAOE 



327. Nereis development 415 



328. Lumbricus agricola . . 418 



329. setse 419 



330. ,, transverse section ... .... 419 



331. ,, herculeus, sagittal section . 420 



332. ,, nervous system 422 



333. ,, nephridium 423 



334. ,, agricola, reproductive organs 424 



335. ,, development 426 



336. Polynoe setosissima 429^ 



337. Vermilia ccespitosa 430 



338. Setre of various Polychceta 431 



339. Section of setigerous sac of an Oligochaete 431 



340. Polynoe extenuata, anterior end 432 



341. Tubifex 433^ 



342. Terebella .... ...... 434 



343. Aphrodite, enteric canal ... 436 



344. Saccocirrus, transverse section 438 



345. Diagram illustrating development of gonad of Polychaeta . . 441 



346. Spirorbis lams 444 



347. Eupomatus, development of trochosphere 445 



348. Autolytus cornutus, budding . . . 446 



349. Serpulse with their tubes 447 



350. Myzostomum 449 



351. ,, .anatomy 450 



352. Sipunculus iiudus, anterior extremity 451 



353. ,, ,, tentacular fold . . ... 452 



354. ,, ,, anatomy 453 



355. ,, ,, nervous system 453 



356. Bonellia viridis, female 456 



357. Echiurus ... 456 



358. Priapulus 457 



359. Bonellia, anatomy 458 



360. Echiurus, ciliated funnel 458 



361. ,, anatomy 459 



62. ,, nervous system . . . .... . . . 459 



363. n.mrllia, male 460 



364. Echiurus, fcrochosphere .... .... 460 



.'I6.V Polygordius neapolitanus 462 



.'Kit). Protodrilus 4^3 



.'>(57. Polygon 1ms iu:;ipolitanus, transverse section . . . 4(53 



365. ,, ,, trochosphere . . ... 464 

 "69. ,, ,, ,, later stage .... 464 



370. Hirudo medicinalis 455 



371. ,, ,, transverse section 468 



372. ,, ,, jaw 468 



,, quinquestriata, dissection from dorsal aspect . . 469 



11 left side .... 470 



375. ,, medicinalis, nephridium 47^ 



