NON NITROGENOUS CELL CONTENTS. 



119 



form of minute drops. Sometimes they 

 nre found in a more or less solid condi- 

 tion, irregular in shape. They should be 

 considered as reserve products, some- 

 times replacing starch and sometimes in 

 comLination with starch, serving ns nu- 

 triment for the young plant after germi- 

 nation. They are, therefore, most often 

 found in the Poods and fruits of plants, 

 less ofton in the stems or roots. 



They nre present in Senega, Gentian, 

 Glyeyrrliiza, Flos. Tilise and Chamo- 

 mile, in most pollen grnins and in the 

 stigmas of Crocus, also in the spores of 

 Lycopodiura and in Ergot. Chemically 

 they are ethers of glycerine formed with 

 the fatty acid scries, or acrylic series. 



Starch is found throughout the vege- 

 table kingdom in large quantities and 

 two types are to be distinguished, As- 

 similated Starch and Reserve Starch. 

 The first has been spoken of under the 

 paragraphs upon the Loucoplasts and 

 the Chromoplasts. The Reserve Starch 

 is the starch of assimilation which has 

 been dissolved and has passed through 



the leaves and into the bark, where it is 



called transitory starch and is in small 

 grains 2-5 mm. in diameter. From here it 

 passes on and is found stored up in the 



roots and stems* tubers and seeds to 

 serve as a reserve food product. This 

 reserve starch is generally in larger- 

 sized grains measuring from 30-200 mm. 



in diameter. 



There are numerous classifications of 

 the starch grain; the most important of 

 these are to be found in Wiesner's Mik- 

 roskopische Technologie and in Xiigeli's 

 Starke Koerner. I here append the 

 classification of Vogel: 



A. Granules simple, bounded by roundeJ 

 surfaces. 



I. Nucleus central, layers concentric, 



a. Mostly rounded or from the side 

 lens shaped. 



1. Large granules, .0396-.0o2.8 nmu 

 Rye starch. 



2. Large granules, .0352-.0.'?!>0 mm. 

 Wheat starch. 



3- Large granules, .02Gi mm. Barley 

 starch. 



b. Egg shaped, oval, kidney shaped. Hi- 

 lum often long and ragged. 



1. Large granules, .032-. 097 mm. 

 Leguminous starches. 



II. Nucleus eccentric, layers plainly ec- 

 centric or meniscus shaped. 



a. Granules not at all or only slightly 



flattened. 



1. Nucleus mostly at the smaller 



end, ,06-.10 mm. Potato starch. 



2. Nucleus mostly at the broader 

 end, or toward the middle in sim- 

 ple granules. .022-.060 mm. Ma- 

 ranta starch. 



b. Granulea more or less ntrongly flat- 

 tened. 



1. Many drawn out to a short jH^iut 



at one end, 



a. At most .060 mm. long. Cur- 

 cuma starch. 



b. As mucb uA A^2 mm. lonff, 

 Canna starch. 



2. Many lengthrnod to bonn shaped, 

 disk phnp<'<l or llntteutNl; nuch'us 

 near the broader end, .iH4-.075 mm. 

 Hunauu sjturcb. 



3. Many strongly kidney shaped; mi- 

 dens near the edge, .048-.u.'.t>. Sl- 

 hrvnchlnm starch. 



4. Egp: sliiii)ed; at one end reduced 

 to u wtdiiL', at the other enlnrredj 

 nnclenf5 at the smaller end, ,05-.0i 

 mm. Yam starch. 



n. Grannies simple or componnd. slncle 

 granuh's or jiarls of grHunl«-v, either 

 bounded entirely by plain surfaces, mnny 

 angled, or by partly rounded surfaces. 

 \. Granules entirely nnpular. 



1. With n prominent nucleus. At 

 most .(KHiG mm. Rice starch. 



2. WUhuut a nucleus. The larg<'st 



.0088 mm. Mill-t starch, 

 H. Among the many aughMl. also round- 

 ed forms. 



a. Few partly rounded forms present, 

 angular form predominating. 



1. Withont nucleus or deprewlon, 

 verv small, .0044 mm. Oat starch. 



2. with nucleus or depret>siou, .01?2- 

 .0220 mm. 



a. Nucleus or Its depression con- 

 siderably rounded; here and 

 there the grannies united into 

 differently formed groups. Buck- 

 wheat starch. 



b. Nucleus mostly radiatory or 

 star shaped; all the granules 

 free. Corn starch. 



b. More or less numerous kettleilrum 

 and sugarloaf-like forms. 



1. Very numerous eccentric layers; 

 the largest granules .022-. 0352 mm. 

 Batata starch. 



2. Without layers or rings, .08-.022 

 mm. 



a. In the kettledrum-shaptKl gran- 

 ules the nuclear depression 

 mostly widened on the flattened 

 side, .U06-.U22 mm. Cassava 

 starch. 



b. Depression wanting or not en- 

 larged. ,, ^ , 



au. Nucleus small, eccentric, 



.006-.016 mm. Pachyrhizus 



Bt£ircli 

 bb. Nucleus small, central or 



wanting, 

 aaa. Many irregular forms, 



.008-.0lt6 mm. Sechinm 



Starch. 



bbb. But few angular 

 forms; some with radiat- 

 ory nucleal fissure, .00ft- 

 .0176. Castanospermum 

 starch. 



C Granules simple and compound, predom- 

 inant forms egg shaped and oval, with ec- 

 centric nucleus and numerous layers, the 

 compound granule made up of a large 

 Tanule and one or more relatively small 

 _ettledrum-shaped ones^ .025-.066 mm. 



Sago starch, 



Amylo-destrin is not found free in nat- 

 ure, but in combination with starch, re- 



