PHAIUS. 



737 



ANILINE REACTIONS. 



With gentian violet the grains immediately color very 

 lightly, and in half an hour they are moderate to deep 

 in color (value 57), with a greater number of the former. 

 The coarser refractive lamellae stain a little more deeply 

 than the other lamellae and also occasionally the hilum 

 is slightly deeper than other parts. The secondary sets 

 of lamellae and the refractive band sometimes present 

 either at the distal margin or at the proximal margin, 

 and about half of the lateral margins, color less deeply 

 than the main body of the grain. 



With safranin the grains immediately color lightly, 

 but somewhat deeper than with gentian violet ; in half an 

 hour they stain moderately to deeply (value 60) with 

 more of the former, but the color is somewhat deeper than 

 with gentian violet. The variations in depth of coloring 

 with this reagent are the same as with gentian violet, but 

 the differences are more marked since the color is slightly 

 deeper than with gentian violet. 



TEMPERATURE REACTIONS. 



The majority of the grains are gelatinized at 65 to 

 66 C., and of all but rare resistant grains at 68 to 69 

 C., mean 68.5 C. The most resistant grains are those of 

 medium size, and the most resistant parts are the outer- 

 most marginal lamella? of the proximal end and sides 

 nearby of all grains. 



EFFECTS OF VARIOUS REAGENTS. 



The reaction with chloral hydrate begins in a few 

 grains immediately. Complete gelatinization occurs in 

 about 20 per cent of the entire number of grains and 30 

 per cent of the total starch in 5 minutes; in about 42 

 per cent of the grains and 50 per cent of the total starch 

 in 15 minutes; in about 60 per cent of the grains and 

 65 per cent of the total starch in 30 minutes; in about 

 75 per cent of the grains and 79 per cent of the total 

 starch in 45 minutes; little if any further progress or 

 about 80 per cent of the total starch in 60 minutes. 

 (Chart D 574.) 



The hilum becomes very distinct, attended sometimes 

 by the formation of a bubble. Two distinct lines, appa- 

 rently fissures, extending from the hilum to the distal 

 corners, and sometimes longitudinal folds or wrinkles, 

 apparently in the capsule, extend from the hilum almost 

 to the distal margin. The lamella? become distinct, espe- 

 cially toward the distal end, and a very distinct refractive 

 band, which is especially broad at the proximal end, 

 quickly forms about the margin of the grain, in which 

 the lamella? have become still more distinct. Gelatiniza- 

 tion usually begins first at the distal and subsequently at 

 the proximal end. In grains with a set of secondary 

 lamellas it begins at the distal end of the secondary 

 set, then at the proximal end, and finally at the distal end 

 of the primary set. Rarely it begins at the proximal 

 end and then shortly at the distal end. It proceeds from 

 both ends toward the most resistant portion of the 

 grain which is usually just distal to the hilum and is 

 preceded always by a pitted appearance of the ungela- 

 tinized parts. Those grains which are very resistant 

 develop several deep, cup-shaped cavities in the ungela- 

 tinized portions which after crumbling into many small 

 pieces are gelatinized. The gelatinized grains are very 

 large and much distorted and do not retain much of the 

 form of the untreated grain. 



The reaction with chromic acid begins immediately. 

 Complete gelatinization occurs in about 4 per cent of the 

 entire number of grains and 30 per cent of the total 

 starch in 5 minutes; in about 20 per cent of the grains 

 and 70 per cent of the total starch in 15 minutes ; in about 

 95 per cent of the grains and in more than 99 per cent 

 of the total starch in 30 minutes. (Chart D 575.) 



The hilum becomes distinct, but without an attendant 

 formation of a bubble. The lamellae, at first distinct, 

 become obscured by the process of fissuring, and then 

 appear very distinct as rows of granules disposed accord- 

 ing to the original lamellar arrangement. A broad re- 

 fractive band is formed about the margin of many grains, 

 the band being broader at the proximal end, and often 

 not present at the distal end. Gelatinization begins at 

 the hilum which enlarges, and the part of the grain just 

 proximal to the hilum rapidly gelatinizes, making a 

 broad, canal-like opening to the capsule. From this 

 beginning gelatinization proceeds by extensive spreading 

 of fine irregular fissures from the hilum to the distal 

 margin. By this means the grain, as a whole, is divided 

 into coarse granules near the hilum and fine granules 

 near the distal end, and this process is promoted by the 

 invasion of the grain by fine fissures which penetrate the 

 grain from the distal margin. As the granules are 

 gelatinized, beginning with those at the proximal end, 

 those more distally placed are found in rows according 

 to the lamellar arrangement. In the meantime the cap- 

 sule at the proximal end and also at several other points 

 is dissolved, but the grain retains much of its form until 

 the granules are reduced to a semi-fluid mass which 

 escapes from the openings in the capsule, and the distal 

 starch is the last to be so gelatinized and dissolved. 

 Some resistant shreds of the capsule persist long after 

 the rest of the grain has been dissolved, but finally these 

 also are dissolved. 



The reaction with pyrogallic acid begins in a few 

 grains immediately. Complete gelatinization occurs only 

 in rare grains, less than 0.5, and 6 per cent of the total 

 starch in 5 minutes ; in about 0.5 per cent of the entire 

 number of grains and 34 per cent of the total starch in 

 15 minutes; in about 16 per cent of the grains and 50 

 per cent of the total starch in 30 minutes; in about 22 

 per cent of the grains and 58 per cent of the total starch 

 in 45 minutes ; in about 28 per cent of the grains and 67 

 per cent of the total starch in 60 minutes. (Chart D 576.) 



The reaction with nitric acid begins immediately. 

 Complete gelatinization occurs in 38 per cent of the 

 entire number of grains and 72 per cent of the total 

 starch in 1 minute; in about 78 per cent of the grains 

 and 95 per cent of the total starch in 5 minutes; in 

 about 87 per cent of the grains and 97 per cent of the 

 total starch in 10 minutes; in about 94 per cent of the 

 grains and over 99 per cent of the total starch in 15 min- 

 utes. ( Chart D 577.) 



The hilum swells and sometimes a bubble appears 

 which may occasionally enlarge considerably. Gelatiniza- 

 tion spreads rapidly through the mesial portion to the 

 distal margin, a marginal border at the proximal end and 

 sides usually being the most resistant. In some grains 

 a small swelling appears, first at the proximal end, and 

 the process then proceeds as above described. 



The gelatinized grains are much swollen and dis- 

 torted, the distal margin is usually telescoped, and the 

 proximal end has sometimes a concave depression. The 



