GENUS MARANTA. 



827 



secondary set of lamellae is much more clearly marked and more frequently observed, and there is 

 greater variation as to direction of its axis, width, and number of lamellae than in M. arundinacea. 



The grains vary in size; the smaller are 4 by 3ju, the larger are 36 by 20^ in length and breadth. 

 The common size is about 26 by 20n in length and breadth. 



Polariscopic Properties. — The figure is eccentric and usually distinct. Its lines are rather fine 

 and cross each other obliquely; they are frequently bent and sometimes bisected. The figure is 

 more eccentric and irregular than in M. arundinacea. 



The degree of polarization is high, but not so high as in M. arundinacea. There is a great varia- 

 tion in the different grains and often in the same aspect of a given grain. The variation in both 

 cases is much greater than in M. arundinacea. 



With selenite the quadrants are generally well de- 

 fined, but not so clean-cut as in M. arundinacea. They 

 are unequal in size and usually irregular in shape, and 

 much more irregular than in M. arundinacea. The colors 

 are more often pure, although there are more grains in 

 which they are not quite so pure as in M. arundinacea. 



Iodine Reactions. — With 0.25 per cent Lugol's solu- 

 tion the grains color a fairly deep reddish to blue-violet, 

 some rather rapidly and others gradually. The tint is 

 a little lighter and redder and deepens a Uttle quicker 

 than in M. arundinacea. With 0.125 per cent solution 

 the grains color a very light reddish to fair blue-violet, 

 which deepens rather rapidly. There is greater varia- 

 tion in the different grains, and they deepen more quickly 

 than in M. arundinacea. After heating in water until 

 the gi-ains are gelatinized and then adding iodine, the 

 solution becomes a deep indigo-blue, and most of the 

 gelatinized grains a deep blue, a few with reddish tint. 

 The grains are colored a deeper and purer blue than in 

 M. arundinacea. If the gelatinized grains are boiled for 2 minutes and then treated with iodine, 

 most of the grain-residues become a fairly deep but rather bright blue, some having a reddish tint; 

 the capsules are a reddish-violet, and the solution a very deep blue. The grain-residues color more 

 deeply than in M. arundinacea. With an excess of iodine the grain-residues become very deep and 

 the capsules a reddish-violet to heliotrope. The color is not quite so red as in M. arundinacea. 



Staining Reactions. — With gentian violet the grains begin to color slightly at once and in 30 

 minutes are lightly colored, lighter than in M. arundinacea. 



With safranin the grains begin to color slightly at once and in 30 minutes are fairly colored, 

 lighter than in M. arundinacea. 



Temperature Reaction. — The temperature of gelatinization is 88° to 89° C, mean 88.5°. 



Effects of Various Reagents. — With chloral hydrate-iodine reaction begins immediately. A few 

 grains are gelatinized in a minute, nearly all in 7 minutes, and all but a few resistant grains in 9 

 minutes, in which the reaction is usually complete in 12 minutes, rarely 20 minutes. The reaction 

 is qualitatively the same as in M. arundinacea, but the old-rose color is purer in tint, the reaction 

 is much slower, and many more grains become a deep wine-red previous to the bluish color that 

 finally spreads over the gelatinized grain. Gelatinization with its accompanying bluish color starts 

 in the way noted for M. arundinacea, but the hilum is much less prominent, appearing usually as a 

 very small, dark dot, and this region is much less resistant since gelatinization from the proximal 

 margin spreads over it and proceeds towards the gelatinized area at the distal end, which, in the 

 meantime, has advanced more rapidly towards the center of the grain. The last portion of the grain 

 to undergo the reaction is distal to the region of the hilum and much nearer the center of the grain 

 than in M. arundinacea. 



The reaction with chromic acid begins immediately. A few grains are dissolved in 2 minutes, 

 nearly all in 7 minutes, all but parts of a few resistant grains in 8 minutes, and all in 11 minutes. 

 The hilum becomes more distinct, but as a rule no bubbles appear there. The lamellae are more 

 sharply defined and striated. According to the shape of the grain the same types of fissures as those 

 described for M. arundinacea are formed, but they are more sharply defined and are observed in 



Curve of Reaction-Intensities of Starch of Maranta 

 musaica. 



