The justification of the following paper is found in the fact that notwithstanding the investigations of Duges (1834), Gegenbaur (1861, 1862, 1876), Hasse (1892), Zykoff (1893), Goeppert (1895), Peter (1895), Gadow (1896), Kapelkin (1900), Schauinsland (1906) and Emelianoff (1925), which deal with the development of the vertebral column in Urodela, there still remains a great deal of uncertainty as to the relationship which exists, first, between the arches, the intervertebral and the vertebral bodies; secondly, as to the exact constituent parts of the neural and the haemal arches; thirdly, as to whether any change takes place in the developing vertebra as it passes from its cartilaginous condition to its ossified stage, for none of the above-mentioned workers has traced the full development to the adult condition; fourthly, as to the development of the first (atlas) vertebra and its relation to the occipital region; lastly, as to how the Urodelan skull has developed two condyles for articulation with the first vertebra. The writer desires to acknowledge his indebtedness to Prof. E. W. MacBrid e, who, with valuable advice and criticism, has greatly facilitated these researches. He has also to acknowledge his obligations to Mr. H. R. Hew er, Mr. N. Murti, Mr. P. Gray, and Mr. C. John for their kind assistance, which has led to the improvement of this paper.