GENUS HYACINTHXJS. 



573 



The reaction with pyrogallic add begins iramediatelj-. A few grains are gelatinized in 10 seconds, 

 the majority in 30 seconds, and all in 45 seconds. The reaction is qualitatively the same as in 

 H. orientalis var. alba superb issirna. 



Reaction with fenic chloride begins at once. A few grains are gelatinized in a minute, the major- 

 ity in 3 minutes, about nine-tenths in 5 minutes, and all but rare resistant grains in 8 minutes. The 

 reaction is complete in these in 15 to 17 minutes. The reaction is qualitatively the same as in H. 

 orientalis var. alba superbissima. 



With Purdy's solution the reaction begins immediately and a few grains are gelatinized in 30 

 minutes. The larger grains are completely, and all the smaller partially, gelatinized in 15 minutes; 

 and three-fourths are gelatinized in 30 minutes. There is practically no further progress in an hour. 

 The medium-sized grains with regular outline are the most resistant. The reaction is qualitatively 

 the same as in H. orientalis var. alba superbissima. 



STARCH OF HYACINTHUS ORIENTALIS VAR. ALBULUS (ITALIAN). 

 (Plate 41, figs. 245 and 246. Chart 161.) 



Histological Characteristics. In form both simple and compound grains are present, with many 

 aggregates consisting usually of from two to five components. Isolated grains with pressure facets 

 are occasionally found, and a few small clumps are observed. The outline of the grain is occasion- 

 ally irregular, which is chiefly due to the presence of a secondary set of lamellie placed at varying 

 angles to the primary set, and rarely to one or more protuberances, rounded or nipple-like, found 

 on the surface. The conspicuous forms are ovoid, ovoid with squared distal end, nearly round, 

 ellipsoidal, and pyriform. There are also grains with rounded pro.ximal end and broadened, flat- 

 tened distal end, some of which approach the clam-shell 

 type, ovoid with pointed distal end, and dome-shaped. 

 When viewed on edge some of the grains are narrower at 

 the distal than the proximal end. There are not so many 

 grains of the transition form to the clam-shell type, nor so 

 many doublets consisting of one large grain and a minute 

 rounded grain, as in H. orientalis var. alba superbissima. 



There is usuallj^ either a cleft or a small cavity at the 

 hilum. Rarely the hilum may be observed as a round re- 

 fractive spot. It is usually two-fifths to one-third eccen- 

 tric. In the round forms it is centric. Sometimes 2 or 

 more hila, without demonstrable lamellte around each, 

 may be observed in a single grain. The fissures are of 

 the same character and arrangement as those noted for 

 H. orientalis var. alba superbissima, but are found in more 

 grains and the cruciate form is more often observed. 



The lamellas are usually quite coarse, and they are less 

 coarse and distinct near the hilum than in other parts of 

 the grain. Wlien demonstrable near the hilum they are 

 observed to form complete rings, but towards tlie distal 



end and the sides thej^ follow the outline of the grain and are probablj' incomplete. One rather 

 coarse, refractive lamella is frequently observed at varying distances from the hilum. There are 10 

 to 12 lamellai in the larger grains. 



The grains vary in size; the smaller are 4 by Sfi; the larger are 32 by 24/u in length and breadth. 

 The common size is 20 by 16/n in length and breadth. 



Polariscopic Properties. The figure is usually eccentric. The arrangement and character of 

 the lines is the same as in H. orientalis var. alba superbissima, except that the double and multiple 

 figures are not so clearly marked antl the lines are more frequently bent. 



The degree of polarization is high. There is a variation in the different grains, as well as some- 

 times in the same aspect of a given grain. It is about the same as in H. orientalis var. alba super- 

 bissima. 



With selenite the quadrants are fairly well defined, usually somewhat irregular in shape, and 

 unequal in size. The quadrants are not quite so clear-cut, and in rather more grains they are irreg- 

 ular and unequal than in H. orientalis var. alba superbissima. The colors are generally pure. 



Curve of Reaction-Intensities of Starch of Hyacinthus 

 orientalis var. albulus (Italian). 



