GENUS NYMPHS A. 



845 



With safranin the grains begin to stain very lightly at once and in 30 minutes are rather lightly 

 stained. The color is less than that of the grains of N. alba. 



Temperature Reaclion. The temperature of gelatinization is 69 to 71 C, mean 70. 



Effects of Various Reagents. With chloral hydrate-iodine reaction begins in 2 minutes. About 

 half the grains are gelatinized in 15 minutes, nearly all in 35 minutes, and all in an hour. It is the 

 same qualitatively as that of the grains of N. alba. 



Reaction with chromic acid begins in some grains in 15 seconds and in the rest in 30 to 60 sec- 

 onds, and is over in 3 minutes. It is the same qualitatively as that of the grains of N. alba. 



The reaction with pyrogallic acid begins in all the grains in 1^ minutes and is over in 6 minutes. 

 It is the same qualitatively as that of the grains of N. alba. 



The reaction with ferric chloride begins in some grains in IJ^ minutes. It is over in nearly all 

 in 30 minutes and in all in 45 mmutes. It is the same qualitatively as that of the grains of N. alba. 



Reaction with Purdy's solution begins in some grains in a minute and in 15 minutes about 

 two-thirds of the total number of grains are partially gelatinized. The reaction is qualitatively 

 the same as in N. alba. 



STARCH OF NYMPH^A ODORATA. (Plate 93, figs. 553 and 554. Chart 363.) 



Histological Characteristics. Inform the grains are simple. No compound grains were observed. 

 There are a few small aggregates, mostly in the form of doublets and triplets, and a few clumps. 

 Some grains have one or more pressure facets. The surface of the grains is rather irregular, owing 

 to the causes noted under A^. alba. The conspicuous forms are oval, ovoid, ovoid with pointed distal 

 end, and roimd; also dome-shaped, rounded oval, either 

 squared or cut off obliquely at the distal end, and vari- 

 ous irregular forms. The grains are not flattened in any 

 diameter. This starch resembles that of A'', gladstoniana 

 more closely than of N. alba, the irregularity of surface 

 being more marked and there being a larger variety 

 of forms. 



The hilum is a fairly distinct, round, refractive spot, 

 centric or nearly centric in the round forms and in the 

 others eccentric one-fifth to one-third, usually one-third, 

 of the longitudinal axis. There are sometimes more than 

 one hilum in a single grain. A crescent-shaped cleft or 

 irregular transverse cavity may be noted at the hilum, or 

 fissures of various characters may be present. The most 

 common fissuration is in the form of a short, curved fis- 

 sure proceeding from each side of the hilum ; or a slightly 

 curved fissure just below the hilum; more rarely two 

 fissures may intersect each other and form a cross, or 

 three fissures may meet at the hilum, or several fissures 

 may be arranged as a stellate figure. 



The lamellce form in some grains coarse, distmct rings or ellipses around the hilum, and are 

 sometunes less promment towards the distal end, while in other grains they are plamly observed 

 throughout the entire grain. They tend to have the shape and irregularities of the outline of the 

 grains when they are located near the distal margin, as in the case of N. alba. Secondary lamellae 

 are sometunes noted. The number of lamellse in some of the large grains is 17. 



The grams vary in size; the smaller are 4 by 4^; the larger are 38 by 30^ in length and breadth. 

 The common size is 24 by 20^ in length and breadth. 



Polariscopic Properties. The figure is centric in a few round grains, but more or less oblique 

 in all other grains. Its lines are distmct and sometimes straight and generally broader and less 

 clearly defined at the margin. They are frequently bent and occasionally bisected, and are more 

 irregular than in N. alba. 



The degree of polarization is fair to high, higher than in N. alba, with less variation among 

 the grains. 



With seknite the quadrants are usually well defined, irregular m shape, and unequal in size. 

 The colors are usually pure. The quadrants are more irregular than in N. alia. 



