THE PHYLUM CHOHDATA 



a single series may seem surprising; however, they do converge as one 

 traces the fossil record back, and many an early Tertiary genus could 

 with equal justification be assigned to either type. Thus their common 

 origin is quite probable. 



REFERENCES 



Berrill, N. J., 1955. "The Origin of the Vertebrates," Oxford University Press, New 

 York, N.Y. An interesting analysis of evidence for the tunicate theory. 



Colbert, E. H., 1955. "Evolution of the Vertebrates," John Wiley & Sons, Inc., New 

 York, N.Y. An interesting and well-illustrated accovmt, from the viewpoint of a 

 paleontologist. 



MiLLOT, J., and J. Anthony, 1958. "Anatomic de Latimeria chalumnae," Centre Na- 

 tional de la Recherche Scientifique. A thorough and beautifully illustrated study of 

 this living fossil, for those who read French with facility. 



Romer, a. S., 1958. "Tetrapod Limbs and Early Tetrapod Life," Evolution, 12, 365- 

 369. The most recent in a series of papers debating the factors which led to the 

 origin of the Amphibia. 



Romer, A. S., 1945. "Vertebrate Paleontogy," 2nd Ed., University of Chicago Press. 

 A classic in its field. 



Romer, A. S., 1959. "The Vertebrate Story," University of Chicago Press. A well- 

 rounded, phylogenetic introduction to vertebrate zoology. 



Smith, J. L. B., 1956. "The Story of the Coelacanth," Longmans, Green & Co., New 

 York, N.Y. The discoverer's account of Latimeria. 



177 



