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 inserted at the back of the slight depression 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. [Illustration: Fig. 49. _Agrostis Spicaventi. c_, “seed,” nat. size; _a_ and _b_, ditto, × about 9. The long slender awn is inserted below the bifid tip of the palea. Nobbe.] In _Arundo_, _Cynosurus_ and some Fescues, where the palea tapers off into a stiff long point, I have not spoken of it as an awn, but have described the palea as tapering into a sharp point (awn-point). It must be admitted that the distinction is somewhat artificial, but it has its advantages in practice. [Illustration: Fig. 50. _Bromus sterilis. a_, “seed,” nat. size; _b_ and _c_, ditto, × about 2. Nobbe. Cf. Figs. 80 and 81.] [Illustration: Fig. 51. _Festuca sylvatica. a_, “seed,” nat. size; _b_ and _c_, ditto, × 8. Nobbe. Cf. Fig. 78.] The rachilla (Fig. 41), when present, often affords good characters, and in a few cases is relied on for the distinction of “seeds” otherwise much alike--e.g. _Lolium perenne_ and _Festuca elatior_; and similarly with the presence or absence of hairs (_Digraphis_, _Arundo_, &c.) or “web” (_Poa_) at the base of the “seed.” (Figs. 55, 69.) On germination the primary root of the embryo usually emerges and at once plunges into the soil, but soon ceases to grow, and the secondary roots (and subsequently adventitious rootlets from the lower internodes) soon give the peculiar fibrous character so well known in grass-roots.