LIST OF ILLUSTRATIONS xxv 



PAGE 



T6. Hirudo, diagram of blood-channels 472 



377. ,, section of eye .... 473 



378. ,, cocoon 474 



379. Three Rhynchobdellida .... 475 



380. Proboscis of Clepsine .... ... .477 



381. Transverse sections of three Leeches . .... 478 



382. Pontobdella, nephridial system . 479 



383. Clepsine, development 47 



384. Diagram of origin of metamerism 482 



385. Diagram illustrating the relationships of the Annulata and Trochel- 



minthes 483 



386. Apus cancriformis, dorsal aspect 485 



387. Lepidurus kirkii, side view 486 



388. Apus glacialis, ventral aspect 487 



389. ,, appendages 488 



390. Lepidurus kirkii, sagittal section 490 



391. Apus, transverse section . . 492 



392. ,, shell-gland 493 



393. ,, cancriformis, nervous system 494 



394. , , structure of paired eye 495 



395. ,, development 496 



396. Astacus fluviatilis, male 499 



397. ,, ,, appendages 501 



398. , , , , articulations and muscles of leg . . . . 503 



399. Section of skin and exoskeleton of Lobster . . . . . 504 



400. Articulations and muscles of abdomen of Crayfish .... 505 



401. Astacus fluviatilis, dissection from right side 506 



402. ,, gills 508 



403. ,, kidney 510 



404. ,, ,, transverse section of thorax .... 511 



405. , , , , diagram of circulation 512 



406. ,, ,, nervous system 513 



407. ,, ,, reproductive organs 515 



408. ,, ,, formation of the blastoderm .... 515 



409. ,, ,, early embryo 516 



410. ,, ,, nauplius . 517 



411. ,, ,, section of embryo 518 



412. ,, ,, advanced embryo 519 



413. Three Euphyllopoda w . . .526 



414. Cladocera 527 



415. Cypris 528 



416. Cyclops and Calocalanus '.. 529 



417. Various forms of parasitic Eucopepoda 531 



418. Argulus foliaceus 532 



419. Lepas anatifera .... .....- 533 



420. Balanus 534 



421. Sacculina carcini ^,,.,,.^===^--1^=^.^^^ . . . 535 



422. Nebalia geoffroyi .... /%j&\ v vL^^\ ' 536 



423. Mysisoculata /flT N TVER SIT Y N ' ' 537 



