MUSA. 



127 



Iodine: 



M. arnoldiana, moderate, value 55. 



M. gilletii, moderate, somewhat less than in M. arnoldiana, value 50. 



M. hybrida, moderate, the same as in M. gilletii, value 50. 

 Gentian violet: 



M. arnoldiana, light to deep, value 50. 



M. gilletii, light to deep, somewhat less, value 46. 



M. hybrida, light to deep, the same as in M. gilletii, value 45. 

 Safranin: 



M. arnoldiana, moderate to deep, value 60. 



M. gilletii, moderate to deep, less than in M. arnoldiana, value 50. 



M. hybrida, moderate to deep, the same as in M. gilletii, value 50. 

 Temperature: 



M. arnoldiana, majority at 60 to 61°, all at 64.5 to 65.8°, mean 65°. 



M. gilletii, majority at 64 to 66.5°, all at 67.5 to 69°, mean 68.4°. 



M. hybrida, majority at 65.2 to 67°, all at 69 to 70°, mean 69.75°. 



In not one of the five reactions are the figures for the 

 two parents the same. The polarization reaction of M. 

 gilletii is higher, and those with iodine, safranin, gentian 

 violet, and temperature are lower than those of the other 

 parent. The hybrid has the same degree of reactivity 

 as M. gilletii in the reactions with iodine, gentian violet, 

 and saJranin ; higher reactivity than either parent in that 

 with polarization; and a lower reactivity in that with 

 temperature. In all of these reactions the hybrid is 

 closer to M. gilletii than to the other parent. In no 

 instance is there intermediateness, and in two records 

 the reactions are in excess or deficit of the parental 

 extremes. 



Table A 41 shows the reaction-intensities in percent- 

 ages of total starch gelatinized at definite intervals (sec- 

 onds and minutes) : 



Table A 41. 



Velocity-eeactiok Cueves. 



This section treats of the velocity-reaction curves of 

 the starches of Musa arnoldiana^ M. gilletii, and M. hy- 

 brida, showing the quantitative differences in the be- 

 havior towards different reagents at definite time-inter- 

 vals. (Charts D 553 to D 573.) 



Among the conspicuous features of these charts are: 



(1) The high to very high reactivity of the starch of 

 Mvsa arnoldiana throughout all of the reactions, in only 

 one of which is the reaction high. In not less than 11 reac- 

 tions out of the 20 at least 95 per cent of the total starch 

 was gelatinized within 3 minutes, and in the others with 

 the exception of chloral hydrate, pyrogallic acid, and 

 barium chloride a similar intensity of reaction occurred 

 in 5 minutes or less. The maximum time (99 per cent 

 in 30 minutes) was in the chloral-hydrate reactions. In 

 many of the reactions not only was the reactivity of this 

 starch greater than in case of the other parent and the 

 hybrid,' but sometimes also markedly higher. 



(2) The marked tendency for the curves of M. gilletii 

 and M. hybrida to run close together, and in many in- 



