170 



CLASSIFICATION OF 



[CH. 



(8 mm.) terminal awn or a mere tooth. Rounded back. 



Fruit grey-brown, ciliate above, 5 — 6 x 1'4 x 07 — 0"9 mm., 



depressed, hardly grooved, adhering to the palea. Rachilla 



smooth or not, and narrowed below. 



A noxious weed (see p. 150) and hence should be carefully 

 excluded from "seeds." 



A. caninum, Beauv., has a longer (10 mm. or more) 

 and rougher awn, and is smaller (about 8 mm.), but 

 otherwise very similar. Palea smooth except at the 

 five-nerved apex. Rachilla thickened above, and hairy 

 (Fig. 75). 



Mymus differs from Agropyrum in its harder velvety palea, no 

 awn, and its club-like velvety rachilla. It is also larger altogether, 

 as a rule. 



Fig. 77. Brachypodium pinnatum. Type of boat-shaped "seed" with 

 awn. a, nat. size; b and c, x 7. Nobbe. Of. Fig. 72. 



