286 DIFFERENTIATION AND SPECIFICITY OF STARCHES. 



Reslio fcrruginosus Link. (Restiacecc.) Dry endosperm . Compound grains spherical to elongated-oval, 

 many somewhat angular as a result of pressure, reticulate, containing about 1000 components. 

 Size about 30^. Separated-grains polyhedral; size 2 to 7//; the larger ones frequently have a 

 small cavity and several delicate radial fissures. 



Anarthria prolifera R. Br. (Restiacece.) Dry endosperm.- Separated-grains polyhedral, sometimes 

 with a very small cavity and delicate radial fissures. Size 1.5 to 7^. Very few free comjiound 

 grains are observed, though they are frequentlj' distinctly perceived in the cells; almost round 

 or oval, by means of pressure more or less polyhedi-al; size about 20/^. The whole cell lumen 

 sometimes appears to be cuneiform filled with separated-grains. 



Pcepalanthus caulescens Kunth. {Eriocaulacere.) Dry endosperm.- Compound grains almost round 

 to elongated-oval, frequently polyhedral, reticulated-granular, or almost homogeneous, con- 

 sisting of about 1000 components. Size 15 to 22/u. Separated-grains polyhedral, the larger 

 ones with a central cavity. Size 1.5 to 8/:. 



Pmpalanthus frigidus Mart. (Eriocaulacece.) Dry endosperm. Starch as in the preceding species. 

 Compound grains containing over 1000 components. Size about 25 to 30//. Separated- 

 grains, size 2 to lOyu. 



Xyris operculata Labill. (Xyridacece.) Dry endosperm. Compound grains spherical or oval, usually 

 more or less polyhedral by reason of pressure, reticulate, containing over 300 components. 

 Size about 30/i. Separated-grains polyhedral; the larger ones sometimes have a small central 

 cavity, and also single delicate radial fissures. Size 2.5 to 10 and 12/i. 



Xyris semifuscata. (Xyridacece.) Dry endosperm. Starch as in the preceding. Compound grains 

 spherical to elongated-conical; containing 400 or more components. Size about 35yu. Size 

 of the separated-grains 2 to 8 and lOfi. 



Mayaai vandellii Schott and Endl. {Xyridacece.) Dry endosperm. Separated-grains, rounded-angular 

 to acute polyhedral ; many have a very small central cavity and single delicate radial fissures. 

 Size 2 to 8 and lOju. The endosperm cells are entirely filled with these polyhedral grains; 

 only indistinct groups may be recognized within these cells, which probably correspond to 

 compound grains. 



Mayaca michauxii Schott and Endl. (Xyridacece.) Dry endosperm. Starch as in the preceding. Sepa- 

 rated-grains polyhedral, usually with a small or large cavity and radial fissures. Size 2.5 to I2fj,. 



Arum orientale Biebrst. (Aroidece.) Dry endosperm. Compound grains rounded or oval, three- 

 fifths to as thick as long, consisting of 4 to 1400 components. Length about 36 and 48/i, 

 thickness al)Out ZQix. Separated-gi-ains polyhedral, usually with acute margins, edges and 

 angles; the larger ones have a central cavity and a few short radial fissures. Size 2 to Wfi. 



Zanledeschia (cthiopica Spreng. ; Kichardia wthiopica Kunth. (Aroidecr.) Dry endosperm. Compound 

 grains spherical to elongated-oval and conical, consisting of 2 to over 400 components. Size 

 about 28m. Separated-grains polyhedral, frequently with a small cavity. Size 2 to 8 and 

 12yii. Simple isolated rounded or elongatcd-oval grains are also ])resent. 



Typha tenuifolia Humb. Bonp. (Typhacew.) Dry endosperm. Compound grains roimiled to oblong- 

 oval, frequently somewhat angular or irregular, reticulated-granular. Size about 15^. Sep- 

 arated-grains more or less polyhedral. Size 2 to 5yu. Poor in starch. 



Piper nigrum Linn. (Piperacece.) Dry endosperm. Compound grains spherical or oval, frequently 

 polyhedral as result of pressure, reticulated-granular, containing over 4000 components. 

 Size about 33^. Separated-grains rounded to polyhedral. Size 1 to 4/i. 



Piper cubeba Linn. fil. (Piperacece.) Dry endosperm. Compound grains spherical or oval, fre- 

 quently by means of pressure polyhedral, reticulate, or with distinct lines of separation, 

 containing over 600 components (most of them have fallen apart). Size about 32/i. Sepa- 

 rated-grains polyhedral, rarely with a small central cavity. Size 3 to lOju. The endosperm 

 cells of Piper nigrum and cubeba are closely packed with starch. When making sections, a 

 few compound grains fall out along with numerous separated-grains. The comjjound grains 

 are a little larger and not so crowded in the innermost less compact tissues of the seed; 

 they are packed in the more external dense tissue, the divisions between the compound 

 grains frequently being indistinctly observed, while in the outermost cells the compound 

 grains consisting of coalesced components form a contin\ious imiform mass having a reticu- 

 lated or parenchymatous appearance (with dense septa and apparently hollow alveoli) as 

 in Amomum, Coinmelina, etc. (See type 12.) 



