LIST OF ILLUSTRATIONS xv 



TAGE 



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 



