10 



Botanical Section 



[PT I 



In noting the shape of the blade the relation of length to 

 breadth, the amount of tapering below or upwards, and the nature 

 of the apex should be considered. Also whether the blade is 

 broadest at its base or near its middle ; and whether the mid-rib 

 is prominent below, forming a keel from the base to the apex 

 (Fig. 12). 



At the base the blade frequently widens out into a ledge-like 

 process, or forms ear-like projections on either side which more 

 or less clasp the stem. These latter are called ears or auricles. 



A B 



Fig. 13. A. Avena sativa, showing the well-developed ligule (lig.) standing up 

 between the culm and the base of the blade (bh). sh. the sheath, x 2. 

 B. Hordeum sativum, showing the well-developed auricles (aur.) clasping the 

 culm (cl.). The short ligule is not shown, x 2. 



At the point where the blade joins the sheath there is usually 

 an erect delicate membranous outgrowth of the latter which 

 partly surrounds the stem or sheath above it. This is called 

 the ligule and may be long or short, pointed or blunt, etc. The 

 presence or absence of the ligule and auricles, and the various 

 characters afforded by them being constant for each species, 

 afford considerable help in the identification of grasses in their 

 non-flowering condition (see Fig. 13). 



In addition to the above points, the student should observe 

 in regard to the foliage: 



(a) The usual position assumed by the blades, i.e. whether 

 erect, drooping, or at right angles to the sheath. 



