LIST OF ILLUSTRATIONS. 



A number of the cuts used in tliis volume have been taken from Clans 

 a.nd Sedgwick's Text-hooh of Zoology ^ by the kind permission oi: the 

 editor, while several cuts relating to botanical subjects have been 

 taken from Prantl and Vines' Text-hooh of Botany. Many of the 

 others, from various' standard works, have been kindly supplied by 

 the publishers of Cassell's Fo-pular Natural History and of Pokorny's 

 Naturgeschichte des ThierreicJis ; Pigs. 1, 5, 7, 8, 9, 10, 11, 12, 13, 20, 

 21, 23, 24, 35, 44, 45, 51, and 133 were drawn for the present volume. 



PAGE 



Fig. 1. All Irritable Plant, the Barberry ... 5 



„ 2. Antherozoids, or Movitig Spores' of Mosses . 12 



„ 3. A moving Plant, Pandorina 'mnrum . . 13 



4. A moving Plant, Volvox . . 14 



„ 6. Typical Cells of Plants . . . . 17 



,, 6. Division of fclie 2^uoleus . . .21 



7. Specimens of Amceha ... 22 



,, 8. Changes of outline of Amceha . . . .22 



,, 9. Otocysts ill the tail of the Opossum Shrimp . 31 



,. 10. Typical Mesoblast Cells . ... 42 



„ 11. Transverse section of Hydra . . . 46 



, 12. Transverse section of Earthworm . . 46 



., 13. Vestigial Gills of embryo Duck . . . -57 



„ 14. Spermatozoa of the Frog .... 67 



,. 15. Ova of a Medusa .... . . 67 



,. 16. Developing Ovum of a Staffisli .... 70 



17 



" -.n'yBlastosphere and G-astrula of .i^lmp/jioasMS . . 70 



„ 19. Larval forms 71 



., 20. Notochord of embryo Duck . . . 73 



„ 21. Conjugation of cells 83 



., 22. A segmented animal, the Opossum Shrimp . 86 



„ 23. Transverse section of embryo Chick : epiblast, 



hypoblast and mesoblast 113 



„ 24. Development of the Spinal Cord of Vertebrates 113 



„ 2-5. A Kummulite . . . . 134 



„ 26. Amcsha 131 



