27 



LINSEED. 



{Linum usitalissimwn, L.) 



Ground linseed is used chiefly as a medicine, but the cake left 

 after extracting the oil is used extensively as a cattle food. This 



ly^ 



Figure 18 

 Fig. 18. Linseed. (1) Pigment cells; (2) Round cells of spermoderm; 

 (3) Fibre cells and (c) cross cells. 



ground cake is usually gray in color, and possesses a more or 

 less characteristic taste or odor. 



There are three characteristics which serve to identify this 

 product. The first is the long, sclerenchymatous cells with 

 pitted walls and a light yellow or straw colored cell content, 

 which are over 100 — 200^ and have a diameter of from 5 — lO/j, 

 when seen in surface view. 



The second characteristic layer of cells is the so-called pig- 

 ment layer. This layer is made up of more or less square cells, 

 with thick, pitted walls and a brown cell content which in the 

 presence of ferric chloride is stained a deep blue. The round 

 cells of various sizes are also particularly noticeable. These 

 have marked intercellular spaces and are easily recognizable, and 

 are of a light yellow color. The elements of linseed noted are 

 shown in Fig. IS. 



SUNFLOWER. 



{Helianthiis annus, L.) 



The seeds or achenes, more properly, of sunflower, are found 

 principally in chick feeds, but in foreign countries particularly 



