LIST OF ILLUSTRATIONS xxiii 



FIfi. PAGE 



279. Starfish, portion of vertical section of arm 351 



280. ,, diagrammatic sections . . . 352 



281. Asterias rubens, digestive system . 353 



282. Astropecten, section of stone-canal .... 354 



283. Anthenea flavescens, dissection from dorsal aspect . . . 355 



284. ,, ,, lateral dissection . . 356 



285. ,, ,, dorsal surface . . . 357 



286. ,, ,, ventral surface . . . 357 



287. Asterina gibbosa, development . . ... 359 



288. ,, \ 360 



289. ,, ,, bipinnaria . . 360 



290. ., 361 



291. ,, exigua, young after metamorphosis . . . 361 



292. Apical system of young Starfish . . . 362 



293. Strongyloceiitrotus . . . 364 



294. Corona of Sea-urchin . . 365 



295. Apical disc of Sea-urchin . . 365 



296. Echinus, lantern of Aristotle . . 366 



297. Sea-urchin, anatomy, lateral view . 367 



298. ,, ,, oral view . . 368 



299. Cucumaria planci ... . 369 



300. Anatomy of a Holothurian . . 371 



301. Antedon ... 373 



302. ,, disc . . 374 



303. , , transverse section of pinnule . . 375 



304. ,, sagittal section . . . 376 



305. Anthenea, ventral view . . 385 



306. Ophioglypha lacertosa . . 386 



307. Astrophyton arborescens . 387 



308. Strongyloceiitrotus .... . 388 



309. Diagram of spine of Sea-urchin . . 389 



310. Pedicellaria of Arbacia punctulata . 389 



311. Hemipneustes radiatus . . 390 



312. Clypeaster sub-depressus . 390 



313. Antedon . . 391 



314. Metacrinus interruptus . . . 392 



315. Development of Echinoderms 397 



316. ,, ,, Antedon ... . . 398 



317. Diagram to illustrate the relationships of the classes of Echino- 



dermata .... ... . . 402 



318. Nereis dumerilii ... . 404 



319. ,, ,, parapoclium . 405 



320. ,, ,, setts . 405 



321. ,, ,, anatomy . . 407 



322. ,, ,, transverse section . . 408 



323. ,, nervous system .... . 410 

 .".24. ,, eye . 411 



325. ,, dumerilii, riephridium . . 412 



326. ,, development .... . 414 



