476 STARCHES OF 1AUA.CKJE. 



With pyrogallic acid the grains begin to react in 10 seconds and are fully gelatinized in a minute. 

 Both hilum and lamellae become very distinct. The hilum swells, and two refractive lines or channels 

 appear and proceed from either side of the hilum towards the corners which limit the distal margin. 

 The lamellae between these lines are very conspicuous and finely striated. Delicate lines now pass 

 from them and also from the base of the gelatinized area around the hilum; the proximal end swells 

 rapidly, and in the ovoid forms it is much extended, while in the broadly triangular grains the path 

 of gelatinization is frequently circuitous. In some grains the striated lamellae at the lateral and 

 distal margins are cut down at several points, so that a sharp, tooth-like lining appears within this 

 outer coating. When gelatinization is complete a convoluted mass remains at the distal end, in 

 which some refractive granules are sometimes found, while bounding the proximal end is the cap- 

 sule and a delicately striated layer which may be slightly invaginated, or wrinkled, or have a slit 

 through the middle. The gelatinized grains do not retain much of the form of the untreated grains. 

 Some are pointed, while others are rounded at the proximal end. In a few grains the swelling is 

 greater in the transverse than in the longitudinal axis. 



With ferric chloride the grains begin to react in a minute. A few are gelatinized in 5 minutes, 

 the majority in 10 minutes, and all in 21 minutes. At first neither the hilum nor the lamellae are 

 distinct. The marginal portion appears as a striated border which is less dense than the central 

 part of the grain, and thus appears darker and less opaque than the latter. The hilum later becomes 

 visible as a clear spot, or at this point a bubble or dark cleft may occasionally appear. The proxi- 

 mal end swells and a flowing movement of gelatinization takes place in which granular starch appears 

 to pass through a cleft in the vicinity of the hilum, invagination usually occurring at this end, the 

 capsule being greatly stretched but apparently not ruptured. Fine radiating lines extend from 

 the comers of the central mass to the sides, and later from the base to the distal margin of the grain, 

 and gelatinization progresses until all is broken down. The gelatinized grain is much swollen and 

 does not retain much of the form of the untreated grain. In the broadly triangular grains the lines 

 passing from the less resistant central part to the corners of the distal margin become larger until 

 a crack results, and the flowing gelatinization movement takes place at these points as well as at 

 the proximal end. Rarely there is an invagination at the distal end, and the lines joining this end 

 with the central, more opaque mass become deepened, and gelatinization starts here. 



Reaction with Purdy's solution begins at once in many grains. It is complete in several within 

 20 seconds and in all in 40 seconds. The hilum and lamellae become very distinct. Gelatiniza- 

 tion of the grain starts around the hilum and the proximal end swells. The outermost lamellar 

 layer undergoes invagination after a short time. The lamellae at the distal end become particu- 

 larly conspicuous and delicately striated. Gelatinization progresses rapidly from the proximal 

 end, and two distinct clear lines proceed obliquely towards the distal margin. From these two 

 main Unes fine lines are given off, and also a cluster of delicate lines pass from the base of the 

 central, less resistant starch towards the distal margin. The entire grain appears to be per- 

 meated by deUcate channels along which gelatinization is taking place, and thus the grain is soon 

 broken down. The gelatinized grain is much enlarged, in most forms being greatly lengthened as 

 well as broadened. Many of the broadly triangular grains undergo considerable extension later- 

 ally during the process of gelatinization. Sometimes a bubble appears at the hilum, as already 

 noted during treatment with the other reagents, and it undergoes changes similar to those observed 

 when the grain is treated with pyrogallic acid. 



STARCH OF LILIUM LONGIFLORUM VAR. GIGANTEUM. (Plate 20, figs. 117 and 118. Chart 98.) 



Histological Characteristics. — In form the grains are simple, isolated, and without pressure 

 facets. They are usually regular in outline. There are some irregularities, caused by rounded, 

 finger-Uke projections from the proximal end, and also by some large, rounded projections from 

 other parts, which projections are often outlined from the main body of the grain by refractive lines 

 which are probably indentations. The conspicuous forms are the broad and narrow triangular with 

 curved base and rounded angles, clam-shell-shaped, and elliptical with both ends round and of the 

 same size, and somewhat irregular elliptical with the distal end broadened and flattened. There 

 are in addition ovoid, pyriform, mussel-shell-shaped, and rod-shaped grains. The small grains, of 

 which there are very few, are round or nearly round. 



The hilum is a small, round or oval, not very distinct spot, with a range of eccentricity varying 

 from one-sixth to one-ninth, usually one-sixth of the longitudinal axis. The hilum is sometimes 



