LIST OF ILLUSTRATIONS 



-♦ 



after Huxley 



FiG. 



1. Duckmole {Ornithorhynchus) ., . . • 



2. Phenacodus, a primitive extinct Mammal — after Cope 



3. Extinct moa and modern kiwi — after Carus Sterne 



4. Crocodiles ..... 



5. Salamander, an Amphibian 



6. Queensland Dipnoan (Ceratodus) 



7. Lancelet, Amphioxus — after Haeckel 



8. Ascidian or sea-squirt — after Haeckel . 



9. Cephalopod (paper nautilus, female) 



10. Fresh-water crayfish {Astacus), a Crustacean 



11. a. Caterpillar ; b, pupa ; c, butterfly 



12. Spider ..... 



13. Crinoid or feather-star 



14. Earthworm .... 



15. Bladderworm stage of a Cestode — after Leuckart 



16. Sea-anemones on back of hermit-crab — after Andres . 



17. Fossil Foraminifera (Nummulites) in limestone — after Zittel 



18. Diagrammatic expression of classification in a genealogical 



tree ...... 



19. Diagram of Vertebrates .... 



20. Diagram of Invertebrates. 



21. Diagrams of reflex actions — modified from Bayliss 



22. Three ciliated cells. .... 



23. A smooth or unstriped muscle-cell, slowly contracting 



24. A piece of striped muscle fibre with its nerve-endings 



25. Diagram of cell structure — after Wilson 



26. Structure of the cell — after Carnoy . " 



27. Fertilised ovum of Ascaris — after Boveri 



28. Diagram of cell division — after Boveri . 



29. Karyokinesis — after Flemming . 



30. Diagrammatic expression of alternation of generations 



31. Diagram of ovum., showing diffuse yolk granules 



xiii 



PA.GE 



2 

 3 

 3 

 4 

 5 

 5 

 6 



7 



9 



9 



9 



10 



10 



II 



II 



12 



13 



15 

 18 



19 



27 

 48 



49 

 50 

 52 

 54 

 55 

 55 

 57 

 65 

 67 



