UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 183 
Contribution from the Bureau of Plant Industry 
WM. A. TAYLOR, Chief 
Washington, D. C. PROFESSIONAL PAPER April 13, 1915 
MORPHOLOGY OF THE 
BARLEY GRAIN WITH REFERENCE TO 
ITS ENZYM-SECRETING AREAS 
By 
ALBERT MANN, Plant Morphologist, and H. V. HARLAN, 
Agronomist in Charge of Barley Investigations 
CONTENTS 
Page 
Page 
1 
Function of the Aleurone Layer . . . . 
18 
Structure of the Barley Grain . . . . 
2 
Greater Diastatic Power of Small-Berried 
Development of the Barley Grain . . . 
5 
19 
8 
21 
Conversion of the Endosperm .... 
9 
27 
Resume of the Conclusions of Other In- 
Modifications Possible by Culture . . . 
28 
10 
30 
Source of Diastatic Ferments .... 
12 
31 
Location of Diastase Secretion .... 
17 
Source of Cytatic and Proteolytic Fer- 
18 
WASHINGTON 
GOVERNMENT PRINTING OFFICE 
1915 
