214 DIFFERENTIATION AND SPECIFICITY OF STARCHES. 



Oreodaphne exaUala Nees; Laurus exallalus Sieb. PI. martin. 100. (Lauraccce.) Dry cotyledons. 

 Grains rounded-oval to elliptical, frequently egg-shaped, frequently somewhat irregular or 

 unsymmetrical; half to as broad as long, the broader ones slightly compressed; no lamellae; 

 hilum about one-seventh eccentric, usually at the narrow end, rarely at the broad end, and 

 occasionally with a longitudinal slit; sometimes with several funnel-shaped fissures radiating 

 from the center of the lamellae. Length about 21^. The two ends of the grain are very often 

 alike in width. 



Laurus nobilis Linn. (Lauracece.) Dry cotyledons. Grains rounded, egg-shaped, frequently some- 

 what irregular, or angular owing to pressure; no lamellae; hilum slightly eccentric, frequently 

 at the narrow end; in place of the hilum there is usually a cavity with more or less numerous 

 short radial fissures, frequently with one marked transverse fissure which divides the grain 

 almost in half. Length 23fi, thickness 19//. Among them some compound grains of few, 

 equal components. (See type 14.) 



Mucuna -pruriens DC. {Leguininosce.) Dry cotyledons. Grains oval or elliptical, usually more or less 

 irregular, the smaller ones almost round; usually half, the longest ones only two-fifths, as 

 broad as long; generally circular in transverse section; the broader ones slightly compressed; 

 no lamellte; in the place of the one-seventh eccentric hilum, a small cavity is found from 

 which delicate fissures pass out in the form of a funnel-like groove. Length 17 to 21/x. The 

 center of these is found at the tapering end; the posterior end being more or less broadened 

 and compressed, sometimes appearing to be cut off, leaving a doubt whether this is a transi- 

 tion type going over into type 8 or whether it is a separated-grain. 



Mucuna wens DC. {Leguminosm.) Dry cotyledons. Grains egg-shaped to rounded-oval, one-half to 

 almost as broad as long, circular in cross-section; no lamellae; at the narrow end a small cavity 

 instead of the one-half eccentric hilum, from this cavity two fissures diverge toward the distal 

 end; and also usually one or more distinct transverse fissures, and sometimes also a few short 

 ones, extend towards the hilum end. Length about 16 to 28/i. Among them some doublets, 

 triplets, and some separated-grains. 



Type 7. Grains Simple, Eccentric, Cone-Shaped. 



Lamellae heaviest and most numerous on one side, and thinnest and least numerous on the 

 diametrically opposite side. Grains more or less conical, almost circular in cross-section. The 

 eccentric hilum toward the broad end. Only a few of the innermost lamelke, as a rule, are complete; 

 the outer ones at the thickened radius seem to be incomplete. On drying, radial fissures are formed 

 which diverge from the center of the lamellae, chiefly toward the distal end, among which one is 

 often noted as coinciding with the median line. Perfect specimens of this type occur very rarely. 

 Generally grains are present in which the distal end (distal to hilum) is tapering, but more or less 

 broadened, approaching the wedge-shaped type (type 8), and sometimes, though rarely, this same 

 end is condensed, or of equal thickness, so as to approach the inverted conical type (type 6) or 

 the rod-shaped type (type 9). 



Schcenus mucroiiatus Linn.; Cyperus wgyptiacus Gloxin. (Cyperacece.) Dry creeping root-stocks. 

 Grains spherical and blunt-triangular to elliptical; frequently conical, or somewhat curved 

 with beak-shaped distal end; two-fifths to as thick as broad; no lamelke; instead of the 

 one-fourth to one-fifth eccentric hilum a small cavity is found from which extend single, 

 short fissures. Length 21/j. Among them, isolated doublets, of unequal halves arising from 

 the cutting off of the tapering distal end. 



Cyperus esculentus Linn. {Cyperacece.) Dry root-stocks. Grains usually conical, rarely rounded or 

 oval; slightly curved at the thin end and frequently with two beak-shaped processes; one- 

 half to almost as broad as long; the broader ones laterally compressed to about two-thirds; 

 no lamelke; hilum at the broad entl, one-third to one-fourth eccentric; occasionally a small 

 or a slit-like cavity. Length about 12 to 14/i. 



Commelina hirsuta R. Br. {Commelinaceoe.) Dry tubers. Grains pear-shaped, or elliptical, or 

 elongated-conical, rarely triangular, frequently somewhat irregular; usually half as broad as 

 long; lamellae numerous and distinct; mostly thickened at the hilum end, the distal end 

 usually i)ointed; and in the triangular grains broailened and squared. Instead of the hilum, 

 a small cavity with radiating fissures; eccentricity about one-tenth. Length about 42//. 

 Some of the grains approach the wedge-shaped (type 8) and the rod-shaped type (type 9). 



