44 



There are three microscopical characteristics which are to be 

 depended on in diagnosing this product, and these are (1) the stone 



Fig 40 

 Fig. 40. Cocoa shells. (1) Stone cells; (2) Cross cells of endocarp and 

 (3) epidermal cells. 



cells; (2) the cross cells of the endocarp and (3) the large, strong- 

 ly walled cells of the epidermis. 



The stone cells are, in surface view, elongated polygonal in 

 shape, having a characteristic dark interior and thick, lighter 

 walls. The cells vary from 15 to 25/x in length and the cell walls 

 vary from 3 — 5fjL in thickness. 



The cross cells are more or less characteristic, also. This 

 layer of cells runs transversely around the seed and are longitud- 

 inally parallel. They are from 10 — 15/x in width and about 200^ 

 long, or sometimes more. 



The cells of the epidermis are large, polygonal in shape and 

 have distinct walls; in size they are from 40 — 50/x in width and 

 about 150 — 200^1 in length. In order to clearly see these cells 

 the specimen should be treated with Javelle water. 



The ground shells have in bulk a peculiar, almost greasy 

 brown color, quite characteristic of this product. Fig. 40 shows 

 the elements of aid to a diagnosis. 



SUGAR BEET PULP. 



This pulp is coming into prominence as a cattle food and is 

 sometimes found in mixtures. In bulk the pulp is whitish grey, 

 with a sweetish odor and somewhat mealy taste. 



Under the microscope the only two characteristics which 

 serve as an aid to its identification are the large, irregularly 

 polygonal cells of the parenchyma which have walls from 3 — 5fj, 

 in width, and the cells sometimes reach a length of 300/x but are 



