LIST OF ILLUSTRATIONS xv 



PAGE 



Fig. 55. Dissection of the roof of the pharynx of Scyllium canicula, 



showing the efferent branchial arteries . . 226 

 ,, 56. Urogenital systems of male and female of Scyllium 



canicula . . . . . .231 



,, 57. Dissection showing the brain, spinal cord, cranial, 



occipital and anterior spinal nerves of Scyllium canicula 237 



,, 58. A series of views of the lower pole of the Frog's ovum . 251 



,, 59. Sagittal sections through developing ova of the Frog . 253 



,, 60. Three views of different developmental stages of the Frog 257 

 ,, 61. Two transverse sections through a young embryo of the 



Frog ... 259 



,, 62. Transverse section through an older embryo . . 261 



,, 63. Longitudinal section through an embryo of the Frog . 263 

 ,, 64. Two horizontal sections through the head and anterior 



part of the body of Tadpoles of different ages . . 265 



,, 65. A Tadpole of the Frog at the time of hatching . . 267 



,, 66. The cranial and visceral cartilages of the Tadpole . 269 

 ,., 67. Transverse sections showing the development of the 



Frog's heart . . . . . .271 



,, 68. Diagrams of the arterial arches of the Tadpole and the Frog 274 



,, 69. Diagrams of the excretory system of the Tadpole . 276 



,, 70. Section through the eye of a Tadpole . . . 281 



,, 71. Diagrammatic section through the skin of a Mammal . 285 

 ,, 72. Tympanic membrane and auditory ossicles of the human 



ear ....... 291 



,, 73. Diagram illustrating the development of the arterial 



arches of Mammals ..... 295 



,, 74. Diagrams of the urogenital system of Mammals . . 299 

 ,, 75. Diagrams illustrating the development of the blastocyst 



and formation of the placenta in Mammals . . 303 

 ,, 76. Diagrammatic transverse section of a pregnant uterus 



illustrating an early stage of placentation . . 305 

 ,, 77. Diagrammatic transverse section of a pregnant uterus 



illustrating the later phase of placentation . . 306 



