LIST OF ILLUSTRATIONS xxvii 



FIG. PAGE 



471. Aphis rosa3 535 



472. Cicada . 585 



473. Pulex and larva 586 



474. Gastrophilus equi ; _ 586 



475. Pieris 586 



476. Crioceris m 587 



477. Section of integument of Insect 588 



478. Mouth-parts of Honey-bee 589 



479. ,, ,, Diptera 590 



480. ,, ,, Lepidoptera 591 



481. Digestive organs of Beetle . 592 



482. Nervous, tracheal, and digestive systems of the Honey-bee . . 593 



483. Tracheal gills of Ephemerid 594 



484. Heart of Cockchafer 594 



485. Nervous system of Diptera 595 



486. Ocellus of Dytiscus larva 596 



487. Chordotonal organ of Isopteryx 597 



488. Sexual apparatus of Honey-bee . . 598 



489. Segmentation of ovum of Insect 599 



490. Germinal layers and amnion of Insect . . . . . . 600 



491. Development of Hydrophilus 601 



492. ,, ,, 601 



493. Apis mellifica, queen, worker, and drone 603 



1:94. Formica rufa 603 



495. Euscorpio 605 



496. Ventral surface of cephalothorax and prae-abdomen of Scorpion . 605 



497. Endosternite of Scorpion 606 



498. Scorpion, anatomy, lateral view 608 



499. ,, ,, dorsal ,, 609 



500. ,, development 610 



501. Embryo of Scorpion 610 



502. Chelifer bravaisii 613 



503. Phrynus 613 



Galeodes dastuguei . . . . . 614 



505. Epeira diadema 615 



506. , , , , chelicerae and pedipalpi of -female .... 615 



507. ,, ,, ,, ,, male . . . .615 

 )8. Sarcoptes scabisei 616 



Trombidium fuligiiiosum 616 



110. Limulus 617 



111. ,, ventral view 618 



>12. Eurypterus fischeri . . .... . . 



)13. Anatomy of dipneumonous Spider . . . ... . . 620 



)14. Limulus, sagittal section - 621 



)15. Lung-book of Spider . 621 



>16. Tracheal system of Spider 



)17. Gill-books of Limulus 



Lateral eye of Euscorpius 622 



Central 623 



