A STUDY OF THE WHEAT HEAD 107 



on the inside. The germ of the kernel is at the base and it faces 

 toward the outside. The crease is on the inside next to the 

 palea. The brush end of the kernel extends upward. There 

 is an undeveloped flower between the two divisions of the 

 spikelet. The attachment of the spikelet to the rachis is 

 called the rachilla. Figure 8 shows all the different parts of 

 the spike. 



Equipment. Heads of wheat sufficient to supply all 

 members of the class. 



Directions. Make two drawings of the entire head of 

 wheat, one showing the side and one showing the edge view. 

 Remove a single well-developed spikelet and make a drawing 

 of it. Draw a single outer glume ; a single flowering glume; 

 and the palea. Make a drawing of the kernel showing the 

 crease side, one showing the germ side, and one showing the 

 cross section. Remove all the spikelets from the head and 

 make a drawing of the rachis. Make all drawings at least 

 four times the natural size except the head and rachis. Make 

 them in careful detail and name all the different parts. 



Fill out the following description for five average-size 

 heads of wheat. 



