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A TEXT-BOOK OF BOTANY. 



the form of yellowish sphero-crystals. If the fresh plant material 

 is placed in alcohol the crystals separate in the form of large 

 needles, often forming branching tufts. When examined by 

 means of the micropolariscope, they polarize light more or less 

 strongly, depending upon how the crystals were prepared. Upon 

 quickly dr)dng the plant material in which it occurs, hesperidin 

 separates in the form of irregular, slightly yellowish clumps, re- 

 sembling those of inulin found in the composite drugs of com- 

 merce. If the material is slowly dried, the crystals are decom- 

 posed. Crystals of hesperidin have been found in Citrus fruits ; 



Fig. 92. Sphero-crystals of inulin. A, parenchyma cells of the root of chicory {Cicho- 

 ritim Inlybus) treated with alcohol: a, numerous small globules shortly after the addition 

 of alcohol; b, a somewhat later stage, showing the fusion of many of the small globules of 

 inulin; c, crystal formation in the globules after the alcohol has acted upon the cells for 

 24 hours. B, sphero-crystals resembling starch grains formed in the tubers of Dahlia vari- 

 abilis in alcoholic material: in b, the section has been treated with nitric acid, the crystal 

 aggregate showing a trichiten structure. — After Dippel in "Das Mikroskop." 



the fruit of Coc cuius laurifolius ; the leaves of Buchu, and Pilo- 

 carpus ; species of Mentha, Hyssopus, Teucrium, Satureia, Tilia ; 

 Conium maculatum ; Scrophularia nodosa, and stamen hairs of 

 the flowers of Verbascum. The crystals are found especially 

 in the epidermal cells of bracts. The crystals in the hairs of the 

 flowers of \'erbascum are usually referred to as a sugar, but, 

 according to the studies of Tunmann, are in the nature of a 

 hesperidin. 



