TABLE OF CONTENTS. 



PAGE 



PREFACE i 



INTRODUCTION i 



1872 



. I. On some points in the Geology of the East Lothian 



Coast. By G. W. and F. M. BALFOUR ... 25 



1873 



II. The development and growth of the layers of the blasto- 

 derm. With Plate I 29 



III. On the disappearance of the Primitive Groove in the 



Embryo Chick. With Plate i 41 



IV. The development of the blood-vessels of the Chick. 



With Plate 2 47 



1874 



V. A preliminary account of the development of the Elasmo- 



branch Fishes. With Plates 3 and 4 ... 60 



1875 



VI. A comparison of the early stages in the development of 



Vertebrates. With Plate 5 112 



VII. On the origin and history of the urinogenital organs of 



Vertebrates 135 



VIII. On the development of the spinal nerves in Elasmobranch 



Fishes. With Plates 22 and 23 .... 168 



/ & ^ 7 



