LIST OF ILLT^STRATIONS 



no. 



PAGE 



415. Nephridium nf Herpobdella . . . 519 



416. Pontobdella, nephridial system . 520 

 417- Clepsine, development . . . . 521 



418. Diagram of origin of metamerism . ... 524 



419. Diagram illustrating the r<4ationships of tlie Aimulata and 



Trochelminthes .... .525 



42(J. A pus cancriforjids, dor.sal aspect , . . . 527 



421. Lepiduru.s kirkii, side view . 528 



422. Apus glacialis, ventral aspect . 529 



423. ,, appendages .... . . . 5.30 



424. Lepidurus kirkii, sagittal section . 5.'-i2 

 42.9. Apus, transverse section . 5.34 



420. ,, .shell-gland . 5.35 



427. ,, cancriformis, nervous .system 536 



428. ,, structure of paired eye . . . 537 



429. ,, development . . . 538 

 4.30. Astaous fluviatilis, male . 540 

 431. ,, ,, appendages . . 543 

 4.32. ,, ,, articulations and muscles of leg 544 



433. Section of skin and exoskeleton of Lobster . . 546 



434. Articulations and muscles of abdomen of Crayfish 547 



435. Astacus fluviatilis, dissection from right side 548 



436. ,, ,, gills . . . 550 



437. ,, ,, kidney . . 552 



438. ,, ,, transverse section of thorax . . 553 



439. ,, ,, diagram of circulation . . 554 



440. ., ,, nervous system . . 555 



441. ,, ,, reproductive organs . . 557 



442. , , , , formation of the blastoderm . . 557 



443. ,, ,, early embryo . . . . 558 



444. ,, ,, nauplius . . . . 5.59 



445. ,, ,, section of embryo . . . 560 



446. „ ,, ,, . . 560 



447. ,, ,, advanced embryo . . 561 



448. Three Branchiopoda . . 571 



449. ,, Cladooera . 572 



450. Cypris . 573 



451. Cyclops and Calocalanus , 574 



452. Various forms of parasitic Eucopepoda ... . 576 



453. Argulus foliaceus . . . . 577 



454. Lepas anatifera . ... 578 



455. Balanus 



456. Sacculina carcini 



457. Nebalia geoffroyi . . , 581 



458. Paranaspides . . 582 



459. Mysjs ooulata . . 582 



460. Diastylis . . 5g3 



461. Gamraarus . , , . ... 584 



579 

 580 



