Tanaka: Citrus Fruits of Japan 



^S2> 



plain color is quite common. Willow- 

 leafed forms associated with elongated 

 fruits also occur from bud variations 

 and often revert to original normal 

 types. 



Perhaps the most striking case of 

 vegetative reversion is presented by 

 the corrugated form of Shilji Mikan, 

 or Spicy Mandarin, in which two dis- 

 tinct forms of fruit and leaves are 

 always found simultaneously on the 

 same plant. These instances suggest 

 the probability that a closer study of 

 bud sports and sexual mutants will 

 reveal the secret of reversion, the 

 phenomenon opposite to original muta- 

 tion. Attention is also called to the 

 important roles which these phenomena 

 may play in the evolution of living 

 organisms, and in the solution of the 

 great problem of the origin of species. 



The study of natural phenomena 

 through the behavior of our economic 



plants is full of interest to the natural- 

 ist. The case of the Wase orange is one 

 of the most interesting in this connec- 

 tion, not only to the student bent upon 

 discovering nature's secrets, but also to 

 the horticulturist ready to apply such 

 discoveries to the material advantage of 

 mankind. Nature is always ready to 

 respond to our appreciation and to 

 reward our interest in her laws. It is 

 to the agriculturist that she seems 

 ready to yield her richest treasures. 



In conclusion may I quote an ancient 

 Japanese poem which presents this very 

 thought: 



"Ametsuchi no Megumi wa tsuneni mujinz6 

 Kuwa de horitore, Kama de karitore." 



which may be rendered in English : 



"To mankind boundless wealth is given 

 By fertile Earth and gracious Heaven. 

 Then dig ye deep into the mold 

 And reap your crop of burnished gold." 



The Place of Heredity in Biology 



Foundations of Biology, by Lor- 

 ANDE L. Woodruff, Professor of 

 Biology in Yale University. Pp. 

 476, 2U figures. New York, The 

 Macmillan Company. 1922. 



It is of genetic interest to find that 

 Professor Woodruff, in putting together 

 what he considers as worth while for 

 "the college student and the general 

 reader" after several years of experi- 

 ence in teaching young men at Yale, 

 has placed unmistakable emphasis upon 

 heredity as one of the important 

 "foundations of biology." This em- 

 phasis did not characterize biological 

 textbooks of a generation ago. 



The chromosome cycle, mutations, 

 Mendelism, sex-determination, linkage 

 and pure lines are among the many 

 topics that are rescued from the closet 

 of the specialist in this excellent book 

 and made common intellectual prop- 

 erty. 



The chapter upon "The Heritage of 

 the Individual," in which the task of 

 selecting the important and discarding 

 the irrelevant in the field of heredity 

 has been admirably carried out, closes 



with the following summary: — "In 

 the first place, it appears clear that the 

 basis of inheritance is in the germinal 

 rather than in the somatic constitution 

 of the individual. A character to be 

 inherited must be innate in the germ 

 cells, and there is no satisfactory evi- 

 dence that modifications of the body, 

 'acquired characters,' can be trans- 

 ferred to the germ and so inherited. 

 Secondly, characters or groups of 

 characters are usually, if not univer- 

 sally, inherited as definite units. These 

 follow Mendelian principles of segre- 

 gation and recombination in the forma- 

 tion of the germ cells of an individual, 

 so that paternal and maternal con- 

 tributions are readjusted in all the 

 combinations which are mathemati- 

 cally possible. And, finally, the germinal 

 factor basis (genes) of unit characters 

 is remarkably constant. Selection is 

 apparently powerless to alter it, but 

 merely sorts out what is already there, 

 or, taking advantage of such changes 

 (mutations) as do occur, determines 

 their survival value for their possessor 

 in the struggle for existence." 



H. E. W. 



