LIST OF ILLUSTRATIONS. XIX 



FIG. TAGE 



66. Diagram of the Condition of the Arches of the Aorta towards the 



Close of Incubation . . . . . . . . . 3 1 6 



67. Diagram of the Arterial System of the Adult Fowl . . . cig 



68. View from above of the Investing Mass and of the Trabeculse on 



^ the Fourth Day of Incubation .226 



69. View from below of the Paired Appendages of the Skull of a Fowl 



on the Fourth Day of Incubation . . . . . .229 



70. Side view of the Cartilaginous Cranium of a Fowl on the Seventh 



Day of Incubation ......... 231 



71. Embryonic Skull of a Fowl during the Second Week of Incubation 



(third stage) from below ........ 234 



