GENUS CRINUM. 



635 



Chart No. 212. 



P I GV 

 S 



inequalities of the surface; and to a slightly concave depression sometimes found at the distal 

 end. The conspicuous forms are elongated ovoid, often with a squared, a concave, or a diag- 

 onal distal end; ovoid, pyriform, ellipsoidal, and nearly round; also triangular with curved base 

 and rounded angles, miLssel-shell-shaped, finger-shaped, quadrangular with rounded angles, and irreg- 

 ular diamond-shaped with proximal end more rounded than the distal end. The grains are usually 

 not flattened. 



The hilum may be a clear round or lenticular spot, eccentric about one-third to one-sixth 

 of the longitudinal axis. It is usually fissured; the fissures are frequently in the form of a crescent- 

 shaped transverse cleft, but sometimes intersect to form a cross or a dragon-fly figure. 



The lamellcB are not usually demonstrable near the hilum, but if apparent they form either 

 fine circular or oval rings at the hilum or mostly follow the outline of the grain when located distally. 

 There is often one more coarse and refractive lamella forming a boundary between the primary 

 and secondary sets of lamellae, and sometimes the more regular grains show two or three such lamellse 

 at varying distances from the hilum. The lamellae are 

 generally more distinct in the distal end over about one- 

 third of the grain, but occasionally may be observed as 

 fine fines over most of the grain. In such grains 24 to 

 26 are often counted, rarely 33 to 42. 



The grains vary in size; the smaller are 3 by 2/i; the 

 larger are 58 by 38/* in length and breadth. The common 

 size is about 44 by 28/i in length and breadth. 



Polariscopic Properties. — The figure is eccentric and 

 distinct. The lines are rather thin and intersect obfiquely. 

 They may be straight, but are often bent and sometimes 

 bisected. Double figures indicating the presence of com- 

 pound grains and aggregates are observed. 



The degree of polarization is high to very high, with 

 variation in the same aspect of a given grain. 



With selenite the quadrants are distinct and fairly 

 clear-cut, but are unequal in size and generally irregular 

 in shape. The colors usually are not pure, having a 

 greenish tint. 



Iodine Reactions. — With 0.25 per cent Lugol's solu- 

 tion the grains color a deep blue-violet which deepens rapidly; with 0.125 per cent solution the grains 

 color a light blue-violet, some lighter than others, which deepens gradually. After heating in water 

 until the grains are gelatinized and then adding iodine the solution colors a deep indigo-blue and 

 the grains a fairly deep bright blue. If the grains are boiled for 2 minutes and then treated with 

 iodine, the grain-residues become a light to fairly deep blue and the solution a very deep blue. With 

 an excess of iodine the grain-residues become a light blue, some with reddish tint, and the capsules 

 a red-violet to heliotrope. 



Staining Reactions. — With gentian violet the grains begin to color immediately and in 30 minutes 

 are lightly stained. 



With safranin the grains begin to color immediately and in 30 minutes are fairly stained. 



Temperature Reaction. — The temperature of gelatinization is 75° to 77° C, mean 76°. 



Effects of Various Reagents. — ^With chloral hydrate-iodine reaction begins immediately. Some 

 small grains are gelatinized in a minute. A small number, including large and small grains, are 

 gelatinized in 5 minutes, about six-sevenths in 10 minutes, nine-tenths in 15 minutes, and all 

 but rare resistant grains (one in many hundred) in 30 minutes. No further change occurred in 

 an hour. The grains immediately color an old-rose, which quickly deepens to a wine-red color. 

 The hilum or the clefts become very distinct and much swollen, and a bubble appears. Gelatiniza- 

 tion accompanied by a dark-bluish color starts at the distal end or at the corners of this margin 

 when the grains are of a broadened form at the distal end, spreads around the margin, and then 

 gradually over the entire grain, accompanied by uniform swelling. When the clefts at the hilum 

 are much swollen, they appear to exert a repellent force upon the advance of gelatinization, which 

 process, after reaching a point near this structure, remains stationary for many minutes. The 

 bubble finally collapses as a whole or disappears in a series of small bubbles, and the region at this 



Curve of Reaction-Intensitiea of Starch of Cnnum 

 fimbriatulum. 



