IRIS. 



647 



swollen and have somewhat thicker capsules than in 

 /. iberica, but not so thick as in I. trojana. They are 

 nearly as much distorted as in I. iberica. In this reaction 

 /. ismali shows qualitatively a closer relationship to I. 

 iberica, than to /. trojana. 



The reaction with calcium nitrate begins in a few 

 grains immediately. Complete gelatinization occurs in 

 about 1 per cent of the entire number of grains and 19 

 per cent of the total starch in 5 minutes ; in about 14 per 

 cent of the grains and 32 per cent of the total starch in 15 

 minutes ; in about 24 per cent of the grains and 48 per 

 cent of t!he total starch in 30 minutes; in about 26 per 

 cent of the grains and 54 per cent of the total starch in 

 45 minutes ; in about 38 per cent of the grains and 62 per 

 cent of the total starch in 60 minutes. (Chart D 392.) 



The reaction with uranium nitrate begins in a few 

 grains in 30 seconds. Complete gelatinization occurs in 

 less than 0.5 per cent of the entire number of grains 

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

 5 per cent of the grains and 14 per cent of the total starch 

 in 15 minutes ; in about 7 per cent of the grains and 22 

 per cent of the total starch in 30 minutes; in about 11 

 per cent of the grains and 29 per cent of t/he total starch 

 in 45 minutes ; in about 15 per cent of the grains and 33 

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

 D393.) 



The reaction with strontium nitrate begins in a few 

 grains immediately. Complete gelatinization occurs in 

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

 10 per cent of the total starch in 5 minutfes; in about 

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

 starch in 15 minutes ; in about 32 per cent of the grains 

 and 68 per cent of the totial starch in 30 minutes; in 

 about 41 per cent of the grains and 80 per cent of the 

 total starch in 45 minutes; in about 50 per cent of the 

 grains and 86 per cent of the total starch in 60 minutes. 

 (Chart D394.) 



The reaction with cobalt 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 less than 0.5 per cent of the 

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

 very slight advance in 30 and 45 minutes; in less than 

 0.5 per cent of the grains and 3 per cent of the total 

 starch in 60 minutes. (Chart D 395.) 



The reaction with copper nitrate begins in a few 

 grains in 30 seconds. Complete gelatinization occurs in 

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

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

 per cent of the grains and 22 per cent of the total starch 

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

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

 18 per cent of the grains and 60 per cent of the total 

 starch in 45 minutes ; in about 23 per cent of the grains 

 and 63 per cent of the total starch in 60 minutes. (Chart 

 D396.) 



The reaction with cupric chloride begins immediately. 

 Complete gelatinization occurs in about 0.5 per cent of 

 the entire number of grains and 5 per cent of the total 

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

 and 22 per cent of the total starch in 15 minutes ; in about 

 12 per cent of the grains and 51 per cent of the total 

 starch in 30 minutes ; in about 25 per cent of the grains 

 and 61 per cent of the total starch in 45 minutes; in 



about the same percentage of the grains and 68 per cent 

 of the total starch in 60 minutes. (Chart D 397.) 



The reaction with barium chloride begins in a few 

 grains in 1 minute. Complete gelatinization occurs in 

 less than 0.5 per cent of the entire number of grams 

 and total starch in 5 minutes ; in less than 0.5 per cent 

 of the grains and 1 per cent of the total starch in 15 min- 

 utes ; in about 0.5 per cent of the grains and 2 per cent 

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

 percentage of the grains and 3 per cent of the total starch 

 in 45 minutes; in about 1 per cent of the grains and 

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

 D 398.) 



The reaction with mercuric chloride 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 3 per cent of the total starch in 15 minutes; 

 in about 1 per cent of the grains and 8 per cent of the 

 total starch in 30 minutes; in about 2 per cent of the 

 grains and 9 per cent of the total starch in 45 minutes ; 

 in about 4 per cent of the grains and 12 per cent of the 

 total starch in 60 minutes. (Chart D 399.) 



31. STARCHES OF IRIS IBERICA, I. CENGIALTI, AND 



I. DORAK. 



Starch of Iris iberica (seed parent) is described in 

 pages 636 to 640. 



IlilS CENGIALTI (POLLEN PARENT). 



(Plates 18 and 19, figs. 107 and 109; Charts D 400 to D 420.) 



HISTOLOOIC PROPERTIES. 



In form the grains are usually simple and isolated, 

 but both compound grains and aggregates are occasion- 

 ally seen. The compound grains belong to but 1 type : 

 3 to 5 or 6 small component grains, each consisting of 

 a hilum and 2 or 3 lamellae, are massed irregularly and 

 surrounded by one common layer of starch. The aggre- 

 gates are generally doublets of equal-sized grains. The 

 grains are usually moderately regular, and any irregu- 

 larities which may occur are due to the following causes : 

 ( 1 ) Shallow depressions and elevations of the distal sur- 

 face and margin, producing a wavy or undulating out- 

 line; (2) a secondary set of lamellae whose longitudinal 

 axis is at a right angle with that of the primary set; 

 (3) deviation of the longitudinal axis and consequent 

 bending of the grain; (4) large or small, rounded projec- 

 tions from the sides or ends; (5) rarely, a narrow notch 

 in the middle of the distal margin. The conspicuous 

 forms are ovoid, and elliptical with flattened distal end. 

 The additional forms are nearly round, triangular with 

 rounded angles, boot-shaped, and club-shaped. The 

 grains are not flattened. 



The hilum when not fissured is a moderately dis- 

 tinct, small, round spot. It is usually fissured, and the 

 fissures have the following forms : (1) A single, straight, 

 transverse line; (2) a flying-bird shape; (3) a V-shaped 

 figure, sometimes crossed by a straight, longitudinal 

 fissure; (4) an irregularly stellate arrangement of fis- 

 sures. The hilum is eccentric from 0.3 to 0.17, usually 

 0.25, of the longitudinal axis. 



The lamellcB are distinct, rather coarse lines. They 

 are continuous,, and are circular in form near the hilum, 

 and in the rest of the grain they usually appear to be 

 discontinuous and follow, in general, the form of the 



