SINAPIS NIGRA 



283 



Prepared Mustard (German Mustard, French Mustard of Mus- 

 tard Paste) is a paste composed of a mixture of ground mustard 

 (either Brassica alba or Brassica nigra, or both) salt, spices and 

 vinegar. 



SINAPIS NIGRA. Brassica Nigra, Black Mustard. The dried, 

 ripe seeds of Brassica nigra (Fam. Cruciferse), an annual occurring 

 much the same as Sinapis alba. 



Description. Campylotropous, ellipsoidal or irregularly spher- 

 oidal, 1 to 1.5 mm. in diameter; externally brownish-red, seed-coat 

 membranaceous, finely pitted, hilum whitish, forming a conical 

 projection, micropyle occurring as a slight depression; . without a 

 reserve layer, hypocotyl curved, cotyledons conduplicate; inodorous: 

 taste pungent and acrid. 



Inner Structure. See Figs. 126 and 128. 



Powder. (Fig. 128.) Yellowish-brown; fragments of seed- 

 coat with mucilaginous epidermal cells; a single layer of thin-walled, 



FIG. 128. Black mustard. A, surface view of some of the characteristic cells 

 seen in the powder: p, elongated stone cells (beaker cells), beneath which is 

 the pigment layer (g); K, endosperm cells containing aleurone; c, cells of 

 cotyledon containing aleurone and oil. B, enlarged surface view of the stone 

 cells, showing a shadow-like reticulum composed of broad lines which appear- 

 ance is due to the fact that some of the cells are tangentially elongated 

 (compare with Fig. 126, B). After Moeller. 



unequal sub-epidermal cells; a layer of palisade or stone cells (so- 

 called " beaker cells "), thickened much the same as in Brassica alba, 

 but of unequal height, giving the section a somewhat reticulate ap- 

 pearance ; a pigment layer of one or two cells which may be tabular 

 or considerably tangentially elongated and with a brown content 

 which is colored blue with ferric chloride, as in flaxseed. The 

 endosperm and embryo contain fixed oil and aleurone grains, these 

 layers practically making up most of the drug. Starch grains are 

 not present in mustard and the powder should not contain more than 

 ten granules to a milligram. 



