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LIST OF ILLUSTRATIONS 



42. 

 43- 

 44. 

 45- 

 46. 



47- 

 48. 

 49. 

 50. 



5i- 

 52. 



53- 

 54. 

 55- 

 56. 



57- 

 58. 



59- 

 60. 

 61. 

 62. 



63. 

 64. 

 65. 

 66. 



67. 

 68. 

 69. 

 70. 



71- 



72. 



73- 

 74. 

 75- 

 76. 



77. 

 78. 



79- 

 80. 

 81. 

 82. 

 83. 

 84. 

 85. 

 86. 

 87. 



90. 

 91. 

 92. 



Triton, pectoral girdle and fore limb . 



Triton, sacrum, pelvic girdle, and hind limb 



Triton, dorsal view of skull . 



Triton, ventral view of skull 



Triton, dissection 



Salamandra, dissection 



Varanus, skull seen from behind 



Lacerta, pectoral girdle and fore limb 



Lacerta, sacrum, pelvic girdle and hind limb 



Lacerta, pectoral girdle and sternum 



Lacerta, dissection 



Kidney formation in amniotes 



Feather, structure 



Columba, pectoral girdle, wing and sternum 



Columba, hind limb . 



Columba, pelvic girdle 



Columba, air-sacs 



Columba, vascular system . 



Dog, skull showing foramina 



Lepus, vertebrae and ribs . 



Lepus, vascular system 



Diagram of arterial arches and vagus nerve 



Lepus, female urinogenital system 



Lepus, male urinogenital system 



Lepus, brain in section and ventral view 



Diagram of mammalian ear 



Development of Amphioxus, early stages 



Amphioxus, origin of notochord, nerve-cord 



Amphioxus, young embryo and larva 



Amphioxus, development of mouth, gill-slits 



Amphioxus, formation of atrium 



Rana, egg showing grey crescent 



Rana, formation and closure of blastopore 



Rana, stages of gastrulation seen in section 



Closed blastopore of Rana and primitive streak 



Rana, origin of mesoderm . 



Rana, origin of notochord and neural folds 



Rana, formation of nerve-tube 



Rana, section showing growth in length 



Rana, origin of the kidneys. 



Rana, origin of the lungs . 



Rana, formation of the gill-slits . 



Rana, origin of the heart 



Rana, development of the eyes . 



Rana, formation of the ears 



Gallus, blastoderm incubated 12 and 15 hours 



Gallus, primitive streak at 10 and 15 hours, 



verse section ...... 



Gallus, primitive streak at 10 and 15 hours, 



tudinal section ..... 

 Gallus, blastoderm incubated 20 hours 

 Gallus, blastoderm incubated 24 hours 

 Gallus, origin of notochord and nerve-cord . 



and 



, and 



of 



seen 



seen 



mesoderm 

 endostyle 



Gallus 



in trans- 

 in longi- 



