HIPPEASTRUM. 



421 



hilum in the untreated grains are soon found, and usually 

 consist of one (intersecting the hilum longitudinally) 

 from which several extensive branches arise, and from 

 these in turn many smaller branches. If the hilum is 

 eccentric, as is often the case, this fissuration spreads out 

 to the distal margin and so divides the substance of this 

 segment of the grain into many fine granules. In the 

 meantime the material at the sides and at the proximal 

 end is divided by fine stria? which radiate from the hilum 

 to the margin. The progress of gelatinization from this 

 beginning is, first, distalward, the granular material 

 being moderately rapidly gelatinized, while the more re- 

 sistant material at the proximal end is pushed to the 

 margin and there forms a broadly striated, lamellated 

 band which becomes transformed into rows of granules 

 as gelatinization progresses and the grain continues to 

 enlarge, and these granules in turn are gradually gela- 

 tinized. Often, however, scattered granules remain in the 

 gelatinized material for a long time after the rest of gela- 

 tinization is complete, and these are gradually gelatinized 

 later. The gelatinized grains are much swollen and 

 usually somewhat distorted, but retain some resemblance 

 to the form of the untreated grain. 



The reaction with potassium sulphide begins in rare 

 grains in 1 minute. Complete gelatinization occurs in 

 less than 0.5 per cent of the entire number of grains and 

 1 per cent of the total starch in 5 minutes ; in about 0.5 

 per cent of the grains and 2 per cent of the total starch 

 in 15 minutes; in about 1 per cent of the grains and 

 3 per cent of the total starch in 30 minutes; very slight 

 progress in 45 minutes ; in about 2 per cent of the grains 

 and 4 per cent of the total starch in 60 minutes. ( Chart 

 D73.) 



The reaction with sodium hydroxide begins in a few 

 grains in half a minute. Complete gelatinization occurs 

 in about 3 per cent of the entire number of grains and 



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



7 per cent of the grains and 18 per cent of the total 

 starch in 15 minutes; in about 20 per cent of the grains 

 and 43 per cent of the total starch in 30 minutes; in 

 about 33 per cent of the grains and 45 per cent of the 

 total starch in 45 minutes; in about 37 per cent of the 

 grains and 52 per cent of the total starch in 60 minutes. 

 (Chart D 74.) 



The reaction with sodium sulphide begins in a few 

 grains in half a minute. Complete gelatinization occurs 

 in about 2 per cent of the entire number of grains and 

 3 per cent of the total starch in 5 minutes; in about 7 

 per cent of the grains and 10 per cent of the total starch 

 in 15 minutes; in about 10 per cent of the grains and 

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

 19 per cent of the grains and 23 per cent of the total 

 starch in 45 minutes ; in about 22 per cent of the grains 

 and 27 per cent of the total starch in 60 minutes. ( Chart 

 D75.) 



The reaction with sodium salicylate begins immedi- 

 ately. Complete gelatinization occurs in about 20 per 

 cent of the entire number of grains and 25 per cent of 

 the total starch in 5 minutes; in about 70 per cent of 

 the grains and 76 per cent of the total starch in 15 min- 

 utes; in about 94 per cent of the grains and 96 per cent 

 of the total starch in 30 minutes; in about 98 per cent 

 of the grains and over 99 per cent of the total starch 

 in 45 minutes. (Chart D 76.) 



A small bubble appears at the hilum, which is more 

 frequently not inclosed within a fissure. Very little 

 expansion of the bubble previous to its expulsion occurs 

 in the majority of grains, but when inclosed within a 

 fissure considerable expansion is often observed, although 

 not uncommonly a cleft already existent at the hilum in 

 the untreated grain becomes enlarged and more refractive. 

 The lamellje do not usually become more sharply de- 

 fined, and a refractive border forms around the main 

 body of most of the grains. Fissures either proceeding 

 from or intersecting the hilum sometimes form during 

 the process of gelatinization ; usually just previous to the 

 expulsion of the bubble. Gelatinization begins at the 

 margin of the grain. When the hilum is centric or but 

 slightly eccentric the process starts almost simultaneously 

 from both ends and then advances towards the hilum, a 

 fissure ploughing its way through this area as the bubble 

 at the hilum is expelled, a narrow band of starch on either 

 side of the area surrounding the hilum proving the most 

 resistant. When the hilum is quite eccentric gelatiniza- 

 tion will begin at the distal margin and the process 

 will then advance towards the proximal end, a narrow 

 border of starch at the proximal end and sides nearby 

 proving the most resistant When a grain has one or more 

 prominent corners gelatinization often begins at these 

 points; or if the grain is rounded a refractive border 

 inclosjng the main body of the grain may become gela- 

 tinized, and then proceed more quickly from one point 

 through the rest of the grain. 



The gelatinized grains are swollen and distorted so 

 that they do not resemble the form of the untreated grain. 



The reaction with calcium nitrate begins in rare 

 grains in 1 minute. Complete gelatinization occurs in 

 less than 0.5 per cent of the entire number of grains 

 and total starch in 5 minutes; in about 1 per cent of 

 the grains and 2 per cent of the total starch in 15 min- 

 utes ; slight progress in 30 minutes ; in about 2 per cent 

 of the grains and 3 per cent of the total starch in 45 

 minutes ; in about 3 per cent of the grains and 4 per cent 

 of the total starch in 60 minutes. (Chart D 77.) 



The reaction with uranium nitrate begins in rare 

 grains in 1 minute. Complete gelatinization occurs in 

 less than 0.5 per cent of the entire number of grains and 

 total starch in 5 minutes; in about 1 per cent of the 

 grains and 2 per cent of the total starch in 15 minutes; 

 in about 2 per cent of the grains and 4 per cent of the 

 total starch in 30 minutes; in about 3 per cent of the 

 grains and 5 per cent of the total starch in 45 minutes; 

 very little if any further advance in 60 minutes. (Chart 

 D78.) 



The reaction with strontium nitrate begins in rare 

 grains in 1 minute. Complete gelatinization occurs in 

 about 0.5 per cent of the entire number of grains and 

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

 1 per cent of the entire number of grains and 3 per cent 

 of the total starch in 15 minutes; in about 3 per cent of 

 the grains and 11 per cent of the total starch in 30 min- 

 utes ; in about 8 per cent of the grains and 19 per cent 

 of the total starch in 45 minutes; in about 14 per cent 

 of the grains and 25 per cent of the total starch in 

 60 minutes. (Chart D 79.) 



The reaction with cobalt nitrate begins in rare grains 

 in 1 minute. Complete gelatiuization occurs in less than 



