A STUDY OF WHEAT. 



under a microscope, or even to get them confused, for they 

 are generally together, and are always the same, whether you 

 find them in flour, in studying the structure of the grain, or, 

 as is too often the case, when we find them where wheat has 

 been used as an adulteration of some ground spice or drug. 



Fig. j. Spiral Vessels found in Wheat. X 400. 



The three coats lie together, but in one direction we see only 

 one layer of cells, while in the opposite we find three- or more. 

 The single layer is the third fruit-coat, while the others are 

 the second and first. On the underside of this fruit-coat, and 

 attached firmly to it, are found very peculiar canals, frequently 

 anastomosing, and having thick walls. They run length- 

 wise of the grain, and in this way give great strength to the 

 fruit-coats. (See Fig. 4.) What remarkable provisions for strength 

 we see in the way these three fruit-coats are arranged. 



4. If you take a grain of wheat and break it open longi- 

 tudinally, breaking it in the crease made by the deep groove, 

 and examine the edges of the epidermis as they fold over in 

 this groove, you will find a line of a deeper color than trie 

 rest of the wheat grain. If this dark line be taken out and 

 treated with potassic hydrate and examined under the micro- 

 acope, s delicate vascular bundle will be seen. (See Fig. 5.) 

 Another sign of strength in the grain. The spiral vessels are 

 seen plainly as they uncoil under the action of the re-agent, 

 as shown on either side of the figure. This vascular bundle 

 is seen plainer near the center of the grain than at either end. 



5. We have divested our grain of its fruit-coats, and have 



