244 DIFFERENTIATION AND SPECIFICITY OF STARCHES. 



Encephnhrtns spiralis Lehm. (Cycadacew.) Dry seed. Grains rounded to oval, sometimes triangu- 

 lar to rcniform, frequently more or less irregular; the broadest ones compressed to about 

 one-third the width; without lamellae and hilum; a longitudinal slit which is quite dis- 

 tinct from the narrow aspect, and rarely visible or less distinct from the broad one; Size 

 15 to 20fi. Among the above are some compound grains of few components. Many of 

 the grains are affected by heat. The starch-grains in the embryo belong to the eccentric- 

 conical type. 



Brachypodium pinnatiim Beauv.; Festuca pinnata Moench.; Bromus rupestris Host. (Graminacew.) 

 Dry seed. Grains rounded to oblong, frequently conical, triangular, or reniform, usually more 

 or less irregular; 1 to 4 times as long as broad; the broad ones compressed; some grains 

 are hollow; from the narrow aspect a longitudinal slit is observed in the compressed forms. 

 Length about ll/x, width 8^. Among the above some compound grains of 2 to 3 components 

 and some separated-grains are observed. Starch as in Bromus. 



Boissierra bromoides Hochst. {Graminacece.) Dry seed. Grains rounded and rounded-triangular to 

 conical and oblong; the broad ones compressed. Size about 1^. Starch as in Bromus. 



Boissierra bromoides Hochst., var. pappophorum pumilio Trin. (GraminacecB.) Dry seed. Grains 

 oval to elongate-lanceolate; one-third to two-thirds as thick as long. Length about 6^., thick- 

 ness about 2.5m. 



Bromus. {Graminacem.) Seed. The grains are simple, usually without lamellae or hilum. Struc- 

 ture rarely distinct, if so always centric, but sometimes more spherical, sometimes more 

 rounded-lenticular, sometimes oval or lanceolate, or even almost terete and compressed. 

 Individual distinctly compound grains consisting of 2 to 3 components rarely occur. In 

 many species, however, there are forms in varying numbers which are somewhat constricted 

 in the middle and may be doublets. 



Bromus madritcnsis Linn. Dry seed. Grains spherical or rounded-oval, occasionally somewhat 

 irregular; many slightlj' compressed, lamellae concentric, delicate and numerous; instead of 

 the hilum a small cavity is observed, which is either rarely spherical and occasionally elon- 

 gated, or frequently flattened; from this cavity a few or numerous fissures radiate; from the 

 narrow aspect a distinct median cleft is very often observed. 



Bromus polystachus DC. Unripe seeds. Grains simple, as in the preceding. 



Bromus maximus Desf. Dry seed. Grains as in Bromus madritensis, usually somewhat smaller 

 in diameter. 



Bromus gussonii Parlat. Dry seed. Grains rounded-oval, rounded-reniform; triangular, very fre- 

 quently somewhat contracted in the middle and thus quadrangular; slightly compressed, up 

 to about half their width; lamella; invisible, or concentric and delicate; from the narrow 

 aspect a longitudinal slit is frequently observed, from the broad aspect occasionally with 

 some radial fissures. Size about 35/i. The grains resemble those of the Hordeaccxe, differing, 

 however, in their more angular (never circular) forms as well as in the lack of small grains. 

 Grains of almost the same size are only found in one cell. 



Bromus rigidus Roth. Dry seed. Grains rounded, reniform, 3 to 4 angles; occasionally somewhat 

 irregular, and frequently somewhat contracted in the middle; slightly compressed up to 

 about half their width; lamellae concentric and delicate, or indistinct; cavity often slit-like, 

 from which a few short radial fissures may emerge. Size about 33 to 40/x. Starch as in 

 Bromus g^issojii. Large starch-grains of seeds from botanical gardens in Berlin (1855) are 

 24 to 29fi, and those from the Paris gardens 20 to 24/;. Otherwise they agree with those 

 above described. 



Bromus xcolgcnsis Jacq. Dry seed. Grains rounded, or rounded-oval, more rarely oval, rounded 

 pear-shaped, or triangular; two-thirds to as broad as long; not at all or slightly compressed 

 with single distinct, concentric lamellae; instead of the central hilum either a rounded or 

 oblong cavity, or rarely a longitudinal slit is observed. Size about Slfi. Also some compound 

 grains of 2 to 4 components are present. 



Bromus squarrosus Linn. Dry seed. Grains rounded to oval, occasionally somewhat irregular; 

 half to as broad as long; the broad ones compressed; occasionally with a central cavity. 

 Length about llyu. 



Bromus arvensis Linn. Dry seed. Grains rounded to oval, slightly compressed; many with a cav- 

 ity. Length about 17/i. 



