LIST OF ILLUSTRATIONS IN THE TEXT. 



PAGE 



Fig. 1. Diagram of the Pigeon with the feathers removed to 

 show the arrangement of the feather tracts (after 



Nitsch) 2 



,, 2. Diagram of the modifications of the deep plantar 



tendons of the feet of birds 2 



3. Base of the skull of CorviUtur albicollis, showing 

 the aegithognathous arrangement of the palate 



bones 3 



,, 4. Base of the skull of Crrus pavonia, showing the 



schizognathous arrangement of palate bones 4 



,, 5. Base of the skull of Serpentarius secretarius, show- 

 ing the desmognathous arrangement of the palate 



bones 5 



,, 6. Base of the skull of Cathartes aura, showing the 

 second type of the' desmognathous arrangement 



of the palate bones 6 



,, 7. Base of the skull of Droiu&us, showing the dromaeo- 



gnathous arrangement of the palate bones 7 



,, 8. Foot of Upupa africana 10 



, , 9. Upupa africana 11 



,, 10. Tail of Irrisor viridis 13 



, , 11 . Irrisor viridis 15 



, , 12. Wing of Cypselus africanus 20 



,, 13. Foot of Cypselus africanus 20 



, , 14. Cypselus africanus 22 



, , 15. Foot of Tachornis parva 28 



,, 16. Tail of Chcetitra stictilcema 30 



,, 17. Foot of Caprimulgus europ&us 31 



,, 18. Caprimulgus fossil 40 



, , 19. Wing of Cosmetornis vexillarius 43 



20. Coracias vwsambicus .. 52 



