xxii LIST OF ILLUSTRATIONS 



FIGDRE PACK 



27. Later Stages in the Development of the Prawn, Pcnais 



potimiriiim m 



28. Metamorphosis of a Barnacle, Lepas 112 



29. Embryos in Corresponding Stage of Development of Shark, 



Fowl, and Man 118 



30. Total Geologic Time Scale 131 



31. Feet and Teeth in Fossil Pedigree of the Horse . . . 135 



32. Four Stages in the Evolution of the Cameline Skull . . 137 



33. Four Stages in the Evolution of the Cameline Fore Foot . 138 



34. Evolution of Head and Molar Teeth of Mastodons and 



Elephants 140 



35. Skull of Java Ape-Man, Pithecanthropus erectus .... 150 



36. Jaws of Man and of the Apes 151 



37. Restoration of Prehistoric Men 153 



38. Neanderthaloid Skull of La Chapelle-aux-Saints . . . 154 



39. Skeleton of Neanderthal Man 155 



40. Diagram of a Typical Cell 192 



41. Diagram of the Early Phases of Mitosis 194 



42. Diagram of the Middle Phases of Mitosis 195 



43. Diagram of the End Phases of Mitosis 196 



44. The Germ Track in Ascaris 201 



45. Diagram of the Germ Track in Ascaris 203 



46. The Germ Track in Miastor 204 



47. Diagram To Illustrate Spermatogenesis 205 



48. Diagram To Illustrate Oogenesis 206 



49. Diagram Showing Parallel between Maturation of 



Sperm-Cell and of Ovum 207 



50. Diagram To Illustrate Fertilization 208 



51. Diagram To Illustrate the Results of Selection in Pure 



Lines 216 



52. An Armadillo Egg Showing Quadruplet Embryos . . . 220 



53. Diagram Showing Chromosome Relations in the Determina- 



tion of Sex 222 



54. A Typical Opposite-sexed Pair of Cattle Twins . . . 230 



55. Diagram Illustrating Behavior of Chromosomes in Men- 



del's Cross of Tall and Dwarf Peas 240 



56. Diagram Illustrating Behavior of First Hybrid Genera- 



tion When Inbred 241 



