_B. pinnatum_ (p. 171) has a much shorter awn, and is nearly glabrous. These grasses are weeds, but are said to occur frequently as adulterants. ΔΔ _Glabrous or nearly so._ ++ _Palea five-nerved, pubescent._ _Agropyrum caninum._ _Agropyrum repens_ is also often awned and may be described here (see also p. 150). _Agropyrum repens_, Beauv. (Fig. 76). [Illustration: Fig. 75. _Agropyrum caninum._ Type of boat-shaped “seed” with sub-terminal awn. _a_, nat. size; _b_, × about 9, but with awn cut short. Rachilla thicker above and hairy; palea not toothed. Nobbe. Cf. Fig. 48.] [Illustration: Fig. 76. _Agropyrum repens._ Awned variety. The awn is very short and sub-terminal: the rachilla smooth. _a_, the “seed,” nat. size; _b_ and _c_, ditto, × about 4-1/2. Boat-shaped “seed” with rounded back. Nobbe. Cf. Fig. 57.] Palea tough, 10-12 mm. long, ovate-lanceolate, 3-5 ribbed and smooth; with a short (2-3 mm.) or long (8 mm.) terminal awn or a mere tooth. Rounded back. Fruit grey-brown, ciliate above, 5-6 × 1·4 × 0·7-0·9 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). _Elymus_ differs from _Agropyrum_ in its harder velvety palea, no awn, and its club-like velvety rachilla. It is also larger altogether, as a rule. [Illustration: Fig. 77. _Brachypodium pinnatum._ Type of boat-shaped “seed” with awn. _a_, nat. size; _b_ and _c_, × 7. Nobbe. Cf. Fig. 72.] ++++ _Palea seven-ribbed, smooth._ _Brachypodium pinnatum._ _Brachypodium pinnatum_, L., is similar, but the palea more open and boat-like and narrows more suddenly above into the smooth awn which is shorter than itself (Fig. 77). Length 8-9 mm. The caryopsis is, however, much more slender than in _Agropyrum_. For distinction from _B. sylvaticum_, see above. The inner palea is ciliate and more delicate than in _Agropyrum_. ≡≡ Paleæ rolled round the “seed” which is terete and tapering gradually into a stiff awn. Δ _Awn longer than the palea._ _Festuca Myurus._ See also _Festuca ovina_, _Cynosurus_, &c., p. 147, and _Arundo_. _Festuca Myurus_, L. (Fig. 80). “Seed” 5-7 mm. without the long (10 mm.) awn, tapering and slender (like _Nardus_), grey or brown. Finely mamillate upwards. Rachilla small. ΔΔ _Awn shorter than palea._ _Festuca ovina_ (var. _rubra_). _Nardus stricta._