CH. l] 



The Morphology of Grasses 



17 



Holcus, Alopecurus, Panicum, etc. 1 In the genus Hordeum the 

 so-called "seeds" often consist of the three united mature 

 spikelets. In a few instances the "seed" consists of the grain 



Fig. 21. I. Central cross-section of a grain of the cultivated Oat, Avena saliva, L. 

 II. A small piece of the peripheral portion more highly magnified. 1 and 2, 

 the pericarp; 3, testa; 4, remains of the nucellus; 5 7, amylaceous tissue; 

 5, gluten cells ; 6 and 7, cells of albumen containing compound starch-grains 

 at 7 they are richer in albumen and poor in starch ; 8, nbro-vascular bundle 

 of the seed-coat. Harz. 



shed free from its palese, as in the common varieties of Wheat, 

 and sometimes Timothy- grass. 



1 For other types see Anthoxanthum and Arrkenatherum. 

 A. 2 



