AGRICULTURAL BOTANY. 433 



successively removed, flowering was prevented, and the leaves and stems 

 became smaller than in the control experiments. 



When the removal of the lateral roots was done at intervals of 4 days for 

 a mouth and after that once a week, the growth of the leaves and stems was 

 not affected, and flowering was promoted. The removal of lateral roots once 

 every week for the first month and once every 2 weeks during the second 

 month resulted in the advance of flowering, but the total number of flowers was 

 not increased. 



When the latei-al roots were removed, the main root was always greatly 

 lengthened, while the stems of the plants were shorter than in the control. 

 When the main root was removed, leaving a few lateral roots, the stems were 

 not affected. 



In the morning glories, peas, and horse beans, the removal of the main root 

 and some of the lateral roots, leaving only a few laterals, caused the flowers 

 to appear earlier than usual and more abundantly. When all the lateral roots 

 were removed, some varieties of peas and the horse beans bloomed earlier, but 

 others were so injured that blooming was not accelerated. 



Where the leaves were removed in the morning glory and l)uckwheat, the 

 plants failed to flower. In the peas, blooming was not promoted, but the bracts 

 seemed to serve as assimilatory organs. 



Rapid transformation of starch into sucrose during' the ripening of some 

 tropical fruits, H. C. P. Geerligs {Intcrnat. Sugar Jour., 10 (1908), No. 116, 

 Pl>. 372-3S0). — On account of the fact that many tropical fruits are as a rule 

 gathered in a green and immature state and allowed to ripen afterwards, the 

 ripening process taking place so rapidly that within a few days they become 

 tender and well-flavored, they are said to offer a good opportunity for studying 

 the somewhat obscure problem of the after-ripening of fruits. Investigations 

 were carried on by the authttr with bananas, mangoes, tamarinds, and sapodil- 

 las to determine the changes taking place during ripening after being re- 

 moved from the plant. A considerable amount of carbon dioxid was given off 

 during this period of after-ripening and important chemical changes were 

 shown to have taken place. 



In the case of the banana the starch is rather suddenly transformed into 

 sucrose, and during this process a little dextrin is formed. In the ripe fruits 

 the sucrose becomes partly inverted or consumed as such or as products of its 

 inversion. 



AVitli the mango, during the process of ripening yellow coloring matter is 

 produced that resembles in every respect carrotin. During the after-ripening 

 the starch is transformed into sucrose, which later on becomes hydrolyzed and 

 splits up into glucose and fructose. The citric acid present in the fruit is vigor- 

 ously attacked, and the decrease in the acid taste is not due to an increase in 

 sugar content, nor to the neutralization of the acid, but to the destruction of 

 the citric acid itself. 



In the ripening of the tamarinds, the starch is transformed into sugar, but 

 in this case it is not changed into sucrose, but into a mixture of glucose and 

 fructose. The increase in the percentage of sugar after the period of maturity 

 is due to the strong concentration by evaporation, as there is no fresh forma- 

 tion of sugar possible in so dry a fruit. 



In the sapodilla the most important change is not due to the saccharification 

 of starch, but to the changes brought about in the tannin and gutta-percha. 

 The amount of sugar before and after ripening is the same, but the fruit 

 becomes palatable by the softening of the hard pectin and by the deposit of 

 tannin and gutta-percha in an insoluble form. 



While studying the ripening of the fruits, the author found a rather sudden 

 transformation of starch into sucrose, followed in a later stage by inversion 



