PREFACE TO THE SECOND EDITION 



During the period since "A New List of the Chromosome Numbers in Vertebrata" 

 appeared in March, 1937, the publication of a complete tabulation of the chromo- 

 some numbers in all animals, both vertebrates and invertebrates, has been 

 increasingly called for in the fields of cytology and genetics. In response to 

 this need, and to incroporate new data, a first edition of "A Review of the 

 Chromosome Numbers in Animals" was published in Tokyo (1949) with the support 

 of the Fourth Special Committee for Researches of Genetics in the Nippon 

 Gakuzyutsu-Shinkokai. This list was mainly based on data obtained up to 1944 

 from Japanese and foreign publications which had appeared up to 1941, but an 

 appendix contained some new data, incompletely collected up to 1948. Furthermore 

 at the request of Japanese investigators, the first edition was originally 

 published in the Japanese language. Unfortunately, it contained many deficiencies 

 and oversights which were mostly due to the unfavorable conditions in postwar 

 Japan under which the list was prepared. Upon the advice of Professor Warren H. 

 Leonard of the Colorado A. & M. College, who suggested that so important a list 

 should be rendered more accessible to biologists in other parts of the world, 

 I prepared the present edition. It represents a revised and enlarged list indexed 

 with the chromosome numbers for 3317 species of animals, namely 2754 species of 

 invertebrates and 5t>3 species of vertebrates, together with the pertinent 

 references. As contrasted with the 2800 species reviewed in the list of the 

 first edition, the present volume obviously has been considerably expanded. The 

 Table of Contents presents a convenient list of the animals included. 



In the present list, the chromosome numbers are tabulated after the fashion of 



the lists "A Review of the Chromosome Numbers in the Metazoa" by E. B. Harvey(l920)^ 



17 Part of this list appeared in 1916, while Part II appeared in the Journal of 

 Morphology, Volume 34, pp. 1-67, 1920. 



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