382 



DATA OF PROPERTIES OF STARCHES OF PARENT- AND HYBRID-STOCKS. 



the width of the border or appear suddenly as a new 

 border; there is not much distortion of the capsule 

 as this border is disorganized and solution of the area 

 gelatinized sometimes quickly follows. When gelatiniza- 

 tion from the distal margin has advanced about one-third 

 to one-half of the length of the grain, it starts in most 

 of the grains in the narrow refractive border at the 

 proximal end and advances rapidly towards the hilum, 

 the bubble expands slightly and is gradually expelled as 

 the reaction reaches the hilum, the most resistant part 

 of the grain being a band of about one-third to one- 

 quarter of the length of the grain, which extends entirely 

 across the grain. In a small number of grains gelatiuiza- 

 tion proceeds almost to the hilum before the reaction 

 at the proximal end has made much progress, leaving 

 only a very narrow area just distal to the hilum at the 

 resistant part of the grain. Gelatinization occurs with- 

 out the previous formation of either clearly defined 

 fissures or the appearance of refractive granules. The 

 gelatinized grains are much swollen, with more dis- 

 tortion at the proximal than the distal end. 



The reaction with calcium nitrate begins in some 

 grains immediately. Complete gelatinization occurs in 

 about 48 per cent of the grains and 9G per cent of the 

 total starch in 5 minutes; in about 80 per cent of the 

 grains and 98 per cent of the total starch in 15 minutes; 

 in about 90 per cent of the grains and over 99 per cent 

 of the total starch in 30 minutes; and in about the same 

 percentage of the grains and total starch in 45 and 60 

 minutes, respectively. (Chart D 14.) 



The reaction with uranium nitrate begins imme- 

 diately. Complete gelatinization occurs in about IT 

 per cent of the grains and 65 per cent of the total starch 

 in 5 minutes; in about 30 per cent of the grains and 91 

 per cent of the total starch in 15 minutes; in about 52 

 per cent of the grains and 95 per cent of the total starch 

 in 30 minutes ; in about 56 per cent of the grains and 96 

 per cent of the total starch in 45 minutes ; and in about 56 

 per cent of the grains and 96 per cent of the total starch 

 in 60 minutes. (Chart D 15.) 



The reaction with strontium nitrate begins imme- 

 diately. Complete gelatinization occurs in about 65 

 per cent of the grains and 98 per cent of the total starch 

 in 5 minutes ; and in about 98 per cent of the grains and 

 over 99 per cent of the total starch in 15 minutes. 

 (Chart D 16.) 



The reaction with cobalt nitrate begins at once. 

 Complete gelatinization occurs in less than 0.5 per cent 

 of the entire number of grains and in 12 per cent of the 

 total starch in 5 minutes; in about 8 per cent of the 

 grains and 52 per cent of the total starch in 15 minutes; 

 in about 21 per cent of the grains and 74 per cent of the 

 total starch in 30 minutes ; in about 26 per cent of the 

 grains and 78 per cent of the total starch in 45 minutes ; 

 in about 30 per cent of the grains and 83 per cent of the 

 total starch in 60 minutes. (Chart D 17.) Gelatiniza- 

 tion begins at the proximal end and proceeds moderately 

 rapidly at first and later very quickly, leaving an area 

 varying from about half of the grains to a very small 

 portion at the distal margin ungelatinized. 



The reaction with copper nitrate begins immediately. 

 Complete gelatinization occurs in about 18 per cent of 

 the entire number of grains and 78 per cent of the total 



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

 and 90 per cent of the total starch in 15 minutes; in 

 about 53 per cent of the grains and 93 per cent of the 

 total starch in 30 minutes; slight progress in about 95 

 per cent of the total starch in 45 minutes; in about 60 

 per cent of the grains and 97 per cent of the total starch 

 in 60 minutes. (Chart D 18.) Gelatinization begins 

 at the proximal end and proceeds rapidly towards the 

 distal margin, practically all of the grains being aifected. 

 The small area at the distal margin is very resistant in 

 many grains. 



The reaction with cupric chloride begins immedi- 

 ately. Complete gelatiuization occurs in about 20 per 

 cent of the entire number of grains and 73 per cent of the 

 total starch in 5 minutes; in about 43 per cent of the 

 grains and 90 per cent of the total starch in 15 minutes ; 

 in about the same percentage of grains and total starch in 

 30 minutes ; in about the same percentage of grains and 

 95 per cent of the total starch in 45 minutes; and in 

 about 47 per cent of the grains and 97 per cent of the 

 total starch in 60 minutes. (Chart D 19.) The reac- 

 tion begins and proceeds simultaneously in many grains. 

 The process starts at the proximal end and advances 

 towards the distal end, a small area at the distal end 

 being very resistant in a number of grains. 



The reaction with barium chloride begins in a few 

 grains in half a minute. Complete gelatinization occurs 

 in less than 0.5 per cent of the grains and of the total 

 starch in 5 minutes; in less than 0.5 per cent of the 

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

 and about the same percentages in 30 and 45 minutes; 

 and about 0.5 per cent of the grains and 2 per cent of the 

 total starch in 60 minutes. (Chart D 20.) 



The reaction with mercuric chloride begins immedi- 

 ately in a few grains. Complete gelatinization occurs in 

 less than 0.5 per cent of the entire number of grains 

 and the total starch in 5 minutes; in about 3 per cent 

 of the grains and 13 per cent of the total starch in 15 

 minutes; in about 6 per cent of the grains and 16 per 

 cent of the total starch in 30 minutes; in about 10 per 

 cent of the grains and 26 per cent of the total starch in 

 45 minutes ; in about 16 per cent of the grains and 40 per 

 cent of the total starch in 60 minutes. (Chart D 21.) 



BKUNSVIGIA JOSEPHINES (POLLEN PARENT). 



HISTOLOGIC PROPERTIES. 

 (Plate 1, figs. 2 and 5; Charts D 1 to D 21.) 



In form the grains are usually simple and isolated; 

 but differ from A. belladonna in that there are a num- 

 ber of small aggregates usually of from 2 to 4 small 

 grains and occasionally from 12 to 14 grains. Compound 

 grains occur much more frequently than in A. belladonna 

 and are more varied in form. They usually consist of 

 two small components, each with its own clearly defined 

 lamella?; and these two grains are joined by common 

 secondary lamella on both sides, but not entirely sur- 

 rounded by them. This curious compound grain may be 

 in turn surrounded by a number of lamellae which prob- 

 ably represent a tertiary deposition of starch. There are 

 also doublets and triplets whose components lie at dif- 

 ferent levels in the inclosing secondary starch forma- 

 tion, and doublets in which a small round grain has be- 

 come adherent to a large ovoid grain, and both have 



