127 Noras and Comment. 



lands, or methods of culture, it would be possible to add 10 per 

 cent or $60,000,000 to one cotton crop. The author discusses 

 differences between local adjustment and breeding, the rela- 

 tion of the former to other variations, methods of introducing 

 new varieties, relation of new place diversities to heredit}-, and 

 other topics of theoretical importance. Among the conclusions 

 that seem worthy of special notice is the following: It is not 

 necessary to believe that the diverse characteristics that appear 

 in a new place represent direct effects of the environm.ent upon 

 the plants. It is more reasonable to suppose that new conditions 

 induce diversity in an indirect manner by disturbing the proc- 

 esses of heredity, and thus allowing ancestral characters that 

 had been transmitted in latent form to return to expression, or 

 c aracters previously expressed to becom.e latent. 



NOTES AND COMMENT. 

 The figure facing page 105 should have appeared in the April 

 number of the Plant World as one of the illustrations of the 

 paper of V. M. Spalding on Plant Associations of the Desert 

 Laboratorv Domain. 



The notes on books and current literature in the present 

 issue, which relate mostly to studies of distribution and the 

 factors involved, have been taken chiefly from late numbeis of 

 the Botanisches Centralblatt with the thought that by their 

 selection in this way the activity of students of distributional 

 problems at the present time mi^ht be most impressively shown. 

 As must always happen when papers from all sources relating to 

 a given subject are considered together, they are of various degrees 

 of permanent value. It is obvious, however, that conclusions 

 based on superficial observation are more and more giving place 

 to well considered and extended investigation, some of the results 

 of which, notably, for example, those of Jaccard, are of far- 

 reaching importance. 



The amount of unwisdom on the subject of nomenclature 

 which working botanists have had to put up with has been so 

 great that by many the whole matter is refused a hearing, and 

 in general this seems to be the only way to preserve one's peace 



