130 SEEDS. 



(66) Mace. 



Mace is the fleshy arillus surrounding the seeds of Myristica 

 fragrans, Houtt. (N.O. Myristicacese), 



Mace consists principally of parenchymatous tissue con- 

 taining numerous oil cells, and traversed by fibre-vascular 

 bundles. 



The cells of the parenchyma (pa) are polygonal and isodia- 

 metric. They contain a remarkable substance, known as amylo- 

 dextrin, embedded in a fatty mass. Amylo-dextiin occurs 

 in grains of very irregular shape. Sometimes they are discoid 

 or rounded but more often they are angular. Solution of 

 iodo-potassium iodide colours them red. 



The oil-cells contain either yellow volatile oil or reddish- 

 brown oleo-resin. 



The epidermis of both surfaces is covered with a thick cuticle. 

 In surface view the epidermal cells (eps, epi) are strongly 

 elongated axially ; they are often fusiform, and have thick 

 walls. Below the upper epidermis there is a collenchymatous 

 hypoderma ; this, however, is not continuous or uniform, but 

 disappears in some places, whilst in others it is composed of two 

 rows of cells. 



The diagnostic characters of powdered mace are : 



(a) The large, pointed, thick-walled cells of the epidermis. 



(b) The oil-cells, many of which may be broken. 



(c) The grains of amylo-dextrin in the parenchymatous 

 cells. 



