654 



STARCHES OP AMARTLLIDACBiB. 



With pyrogaUic acid the reaction begins immediately. A few grains are gelatinized in 30 sec- 

 onds, nearly all in 3 minutes, all but rare resistant grains in 4 minutes, and all in 5 minutes. The 

 reaction is quaUtatively the same as in L. mstivum. 



Reaction with ferric chloride begins in a few grains in a minute. A small number are gelatinized 

 in 5 minutes, about one-third in 15 minutes, three-fifths in 30 minutes, and four-fifths in 60 minutes. 

 The reaction is qualitatively the same as in L. astivum. 



The reaction with Purdy's solution begins in a few grains in 30 seconds. A small number are 

 gelatinized in 5 minutes, with very slight progress occurring in 60 minutes. About one-twelfth are 

 gelatinized in this time, the proportion being larger than in L. cestivum. The reaction is qualita- 

 tively the same as in L. CEstivum. 



Differentiation of Certain Starches of the Genus Leucoium. 



HlSTOLOGICAI. ChAKACTEBISTICS. 



Conspicturus Forms. 

 L. aslwum: Usually simple, few aggregates and com- 



pounds, few pressure facets; somewhat irregular. 

 Inegular ovoid, nearly round, oval, elliptical, bean- 

 sha^d, museel-shell-shaped and clam-shell-shaped, 

 pynform, and lenticular. Flattened when seen on 

 edge, narrower at distal than at proximal end. 

 L. vemttm: Essentially the same as in L. cestivum. 



HHum — Form, Number, and Position. 



L. cestivum: Form clear, round or lenticular spot, usually- 

 fissured, clefts deep and frequently ragged. Posi- 

 tion about 0.33 to 0.25 eccentric of longitudinal 

 axis. 



L. vemum: Form essentially the same as in L. astivum. 

 Position the same as in L. cestivum. 



Lametlce— General CharacUxislics and Number. 



L. cutivum: Not distinct, iisually one very distinct; fine 

 circles around hilum, but farther out follow the 

 contour of grain. 24. 



L. vemum: Essentially the same as in L. cestivum, but 

 rather less indistinct, as a whole. 28. 



Size. 



L. cestivum: From 2 to 60^, commonly 30 by 38/1. 

 L. vemum: From 2 to 60m, commonly 30 by 36ju. 



POLABISCOPIC PBOPERTIES. 



Figure. 



L. cestivum: Usually eccentricj fairly distinct, lines 

 broad and intersect obliquely, may be bent or 

 bisected. 



L. vemum: The same as in L. (estivum. 



Degree of Polarization. 



L. cestivum: High, range from fair to very high. 

 L. vemum: Hi(^, ranges from fair to very high, slightly 

 lower than in L. cestivum. 



Polarization with Selenite — Quadrants and Colors. 



L. aestivum: Quadrants fairly clear-cut, usually irregular 

 in shape, imequal in size. Colors, blue pure, yellow 

 not quite pure. 



L. vemum: Quaorants the same as in L. cestivum. Colors 

 the same as in L. astivum. 



Iodine Reactions. 



Intensity and Color. 

 L. cestivum: Rather deep; violet with reddish tint. 

 L. vemum: Rather deep, slightly less than in L. cestivum. 

 Color slightly redder than in L. cestivum. 



Staining Reactions. 

 With Gentian Violet. 

 L. cestivum: Very light. 

 L. vemum: Very light, the same as in L. cestivum. 



With Safranin. 

 L. cestivum: Light. 

 L. vemum: Light, the same as in L. cestivum. 



Temperature op Gelatinization. 

 L cestivum: 72 to 73° C, mean 72.6°. 

 L. vemum: 71 to 72° C, mean 71.5°. 



Effects op Variotis Reagents. 



Reaction with Chloral Hydrate-Iodine. 



L. cestivum: Begins immediately; complete in five-eighths 



in 15 minutes and in nearly all in 30 minutes. 

 L. vemum: Begins immediately; complete in three-fifths 

 in 15 minutes, and in nearly all in 30 minutes. 



Reaction with Chromic Acid. 

 L. cestivum: Begins immediately; complete in nearly all 



in 5 minutes. 

 L. vemum: Begins immediately; complete in nearly all 



in 4 minutes. 



Reaction with PyrogaUic Acid. 

 L. cestivum: Begins immediately; complete in nearly all 



in 4 minutes. 

 L. vemum: Begins immediately; complete in nearly all 



in 3 minutes. 



Reaction with Ferric Chloride. 



L. cestivum: Begins in a few in a minutej complete in 

 three-fourths in 30 minutes and in six-sevenths in 

 60 minutes. 



L. vemum: Begins in a few in a minute; complete in three- 

 fifths in 30 minutes and in four-fifths in 60 minutes. 



Reaction with Purdy's Solution. 

 L. aestivum: Begins in a few in 30 seconds; little reaction 



in 60 minutes. 

 L. vemum: Begins in a few in 30 seconds; little reaction 



in 60 minutes. 



NOTES ON THE STARCHES OF LEUCOIUM. 



The Leucoium starches are closely alike, and apart from the slight variations in the dis- 

 tinctness and number of the lamellae no differences of note were recorded. They also agree closely 

 in their reactions. L. mstivum has the higher degree of polarization, the higher reaction with iodine, 

 the higher temperature of gelatinization (1° difference), and somewhat less sensitivity to chromic 

 acid and pyrogaUic acid. The differences throughout are slight, which is in accord with the close- 

 ness of the species botanically. 



