130 



TERMINAL AWN 



[CH. 



straight, hooked, or kneed (i.e. sharply bent) ; twisted or 

 not ; smooth or serrulate. They may be inserted at the 

 base or near the middle of the back of the investing 

 palea, or glume, or near its apex, as indicated by the 

 terms basal, dorsal, sub-terminal (see Figs. 47 — 50). 



Some difficulty arises in connection with terminal 

 awns. In some cases there is a true 

 awn — i.e. a distinct bristle or hair 

 — at the apex of the palea, and 

 apparently continuing its substance 

 without interruption ; but in most 

 instances close examination shows 

 that this awn arises from between 

 two minute teeth, and is really in- 

 serted at the back of the slight de- 

 pression between them — e.g. Lolium 

 temulentum (Fig. 48), Brachypodium 

 pinnatum (Fig. 77), &c. 



In another class of cases the awn 

 appears to be really the prolongation 

 of the palea — e.g. Nardus (Fig. 81), 

 Festuca Myurus (Fig. 80), &c. — and 

 when it runs out into a distinct 

 bristle we may speak of a terminal 

 awn without staying to discuss 

 whether or no it is really terminal 

 in development. 



In Arundo, Gynosurus and some 

 Fescues, where the palea tapers oflf into a stiff long point, 

 I have not spoken of it as an awn, but have described the 



Fig. 49. Agrostis Spica- 

 venti. c, "seed,"iiat. 

 size; It and 6, ditto, 

 X about 9. The long 

 slender awn is insert- 

 ed below the bifid tip 

 of the palea. Nobbe. 



