BEGONIA. 



717 



hilum is eccentric from 0.3G to 0.15, usually 0.2, of the 

 longitudinal axis. This is 0.03 less eccentric than in 

 B. socotrana and 0.06 more than in B. double deep rose. 

 In the character of the hilum B. success shows a closer 

 relationship to B. double deep rose, and in degree of eccen- 

 tricity to B. socotrana. 



The lamella are somwhat more distinct than in B. 

 socotrana, but much less distinct than in B. double deep 

 rose. They are usually as fine as in B. socotrana, but 

 are somewhat less irregular in outline than in that grain. 

 Otherwise in arrangement and character they are the 

 same as in B. socotrana. The number counted on the 

 larger grains varies from 30 to 40, usually 36. 



In the character, arrangement, and number of the 

 lamellae B. success shows a closer relationship to B. soco- 

 trana than to B. double deep rose. 



In size the grains vary from the smaller which are 

 0.6 by 0.6/i, to the larger which are 48 by 20/j., in length 

 and breadth. The common sizes are 30 by 15/j. and 28 

 by 19/i, which are, respectively, 2 by I/* and 2 by 2/* less 

 than the corresponding common sizes of B. socotrana, 

 and, respectively, 6/* longer by 4/t narrower and 8p longer 

 than corresponding sizes in B. double deep rose. In size 

 B. success shows a closer relationship to B. socotrana 

 than to B. double deep rose. 



POLARISCOPIC PROPERTIES. 



The figure is as distinct and as well defined as in 

 B. socotrana. The lines cross at an acute angle which 

 does not vary greatly in the different grains, and are 

 usually not bent, but sometimes are bisected as in B. 

 socotrana. 



The degree of polarization varies from moderate to 

 high (value 60), the same as in B. socotrana and 10 units 

 more than in B. double deep rose. 



With 'selenit'e the quadrants are as clear-cut and as 

 regular in form as in B. socotrana. The colors also, as in 

 that starch, are usually pure, except those which show 

 a greenish tinge. 



In the character of the figure, the degree of polariza- 

 tion, and the appearances with selenite B. success shows 

 a much closer relationship to B. socotrana than to B. 

 double deep rose. 



IODINE REACTIONS. 



With 0.25 per cent Lugol's solution the grains all 

 color a light to moderate violet (value 30), the same as 

 in B. socotrana and 15 units less than in B. double deep 

 rose. With 0.125 per cent Lugol's solution the grains 

 all color a very light violet as in B. socotrana and less 

 than in B. double deep rose. After heating in water until 

 all the grains are completely gelatinized and then treating 

 with an excess of a 2 per cent Lugol's solution, the gela- 

 tinized grains are all colored a light to moderate, or 

 deep indigo as in B. socotrana, and more than in B. 

 double deep rose; the solution is colored a deep indigo 

 as in B. socotrana and less than in B. double deep rose. 

 If the preparation is boiled for 2 minutes and then treated 

 with an excess of a 2 per cent Lugol's solution, the grain- 

 residues all color a moderate indigo in their proximal 

 ends as in B. socotrana and more than in B. double deep 

 rose; the capsules a moderate to deep violet less than in 

 B. socotrana, but more than in B. double deep rose, and 

 the solution a very deep indigo as in both parents. 



Qualitatively and quantitatively the reactions with iodine 

 show a closer relationship to B. socotrana than to B. 

 double deep rose. 



ANILINE REACTIONS. 



With gentian violet the grains all color very lightly 

 at once, and in 30 minutes they are lightly to moderately 

 colored (value 40), the same as in B. double deep rose 

 and 5 units more than in B. socolrana. 



With safranin the grains all color very lightly at 

 once, and in 30 minutes they are moderately to deeply 

 colored (value 60), the same as in B. double deep rose 

 and 5 units more than in B. socotrana. 



In the reactions with aniline stains B. success shows 

 a much closer relationship to B. double deep rose than to 

 B. socolrana. 



TEMPERATURE REACTIONS. 



The temperature of gelatinizatiou of the majority 

 of the grains is 63 to 64 C., and of all is 68 to 

 69 C., mean 68.5 C., which is 0.7 C. more than in 

 B. double deep rose and 12.9 C. less than in B. 

 socotrana. The temperature of gelatinization of B. suc- 

 cess is much closer to that of B. double deep rose than 

 to that of B. socotrana. 



EFFECTS OF VARIOUS REAGENTS. 



The reaction with chloral hydrate begins imme- 

 diately. Complete gelatinization occurs in about 70 per 

 cent of the grains and 86 per cent of the total starch in 

 5 minutes ; in more than 99 per cent of the grains and 

 total starch in 10 minutes. (Chart D 539.) 



The hilum and lamella? are not visible as in B. soco- 

 trana. The grains become more refractive after the 

 addition of the reagent and the first part to show this 

 is a rather narrow band of starch at the margin which 

 is as refractive as in B. double deep rose and more refrac- 

 tive than in B. socotrana. Gelatinization begins at the 

 distal end, and in a smaller majority than in B. double 

 deep rose, immediately afterward at the proximal end. 

 In a larger minority than in B. double deep rose it 

 advances only from the distal end and the proximal end 

 is the last part of the grain to be gelatinized. The 

 processes, however, are the same as in B. double deep rose 

 in both methods. The gelatinized grains are as much 

 swollen, have as thick capsules, and are as much distorted 

 as in B. double deep rose. In this reaction B. success 

 shows qualitatively a somewhat closer relationship to 

 B. double deep rose than to B. socotrana. 



The reaction with chromic acid begins immediately. 

 Complete gelatinization occurs in about 20 per cent of 

 the grains and 73 per cent of the total starch in 5 min- 

 utes ; in about 67 per cent of the grains and 95 per cent 

 of the total starch in 15 minutes. (Chart D 540.) (See 

 pages 704 and 707.) 



The hilum and lamellae are as distinct as in B. soco- 

 trana. Gelatiuization begins at the hilum and proceeds 

 very much as in B. double deep rose, except that in a 

 moderate minority of the grains the starch between the 

 2 fissures is not fissured or divided into granules, but 

 simply rapidly gelatinized, causing the marginal band at 

 the distal end to be much broader and thicker than at the 

 proximal end and sides. In this reaction B. success shows 

 qualitatively a closer relationship to B. double deep rose 

 than to B. socotrana. 



