COLORING-MATTERS OF FRUITS. 177 



498. The berries of a common house-plant, JSolanuin Pseudo- 

 capsicum, furnish excellent material for the examination of the 

 coloring-mutters of fruits. The following account, condensed 

 from Kraus, 1 will show the essential characters of the color- 

 granules in this case, and it should be compared with what has 

 been already said about the structure of chlorophyll granules 

 and leucoplastids (168 et seq.}, as well as with the account of 

 the chromoplastids in the parts of flowers (477). 



A section through the ripe pericarp shows that it consists of 

 twenty to thirty or more layers of cells, in most of which color- 

 granules occur. In the outermost cells the granules closely 

 resemble both in form and structure ordinaiy granules of chloro- 

 phyll. In some of the granules the coloring-matter is evenly 

 diffused through the whole mass, while in others it is confined 

 to some one part, the rest of the granule remaining without color 

 of any kind. In these cases the colored and the uucolored parts 

 are not very sharply divided from each other. 



499. Other granules less like chlorophyll-granules occur, in 

 which there is a sharp demarcation between the colored and 

 uncolored parts ; such have been shown to be vacuolar, the 

 vacuoles assuming widely different shapes. These are abundant 

 in the cells which lie five to eight layers, or rather more, from 

 the outside. 



In some of these the colored portion appears spindle-form or 

 sickle-form, in others curved twice, like the letter S. It fre- 

 quently happens that several of these long granules are placed 

 end to end, forming an irregular chain. 



500. In the part of the berry which envelops the seeds the 

 color-granules are extremely slender, and needle-shaped. 2 All 

 of the granules lie in the protoplasm; usually in greatest 

 number in that lining the walls, and immediately around the 

 nucleus. 



501. Occasionally in the larger pericarp-cells roundish col- 

 ored objects are met with, which close examination shows are 

 nothing but vacuoles in the protoplasm of the cell filled with 

 colored sap; sometimes these have been mistaken for the 

 granules themselves, but they can usually be distinguished from 

 them without difficulty, on account of the distortion which they 

 undergo upon slight pressure. 



1 Kraus: Pringsheim's Jahrb., 1872, p. 131. 



2 Trecul : Ann. des Sc. nat., ser. 4, tome x, 1858, p. 154. Weiss: Site. d. k. 

 Akad. Wien, 1864 (Band 1.), and 1866 (Band liv.). 



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