ILLUSTRATIONS

FIG. Page
1.Hyoid Arch of the Conger. (Original.)[58]
2."Vertebra" of a Pleuronectid. (Geoffroy.)[61]
3.Abdominal Segment of the Lobster. (Geoffroy.)[63]
4.Ideal Typical Vertebra. (Owen.)[102]
5.Natural Typical Vertebra. (Owen.)[103]
6.The Archetype of the Vertebrate Skeleton. (Owen.)[105]
7.Ideal Transverse Section of a Vertebrate Embryo. (Von Baer.)[119]
8.Gill-slits of the Pig Embryo. (Rathke.)[134]
9.Meckel's Cartilage and Ear-ossicles in Embryo of Pig. (Reichert.)[145]
10.Cranial Vertebræ and Visceral Arches in Embryo of Pig. (Reichert.)[148]
11.Embryonic Cranium of the Adder. (Rathke.)[152]
12.Transverse Section of Chick Embryo. (Remak.)[211]
13.Development of the Ascidian Larva (Kowalevsky.)[272]
14.Transverse Section of the Worm Nais. (Semper.)[280]
15.The Five Primary Stages of Ontogeny. (Haeckel.)[292]