GROUP IV. PHANEROC4AMIA : ANGIOSPERMJ3 : MONOCOTYLEDONES. 549 



Avena, the Oat-Grass, has loose panicles, and a two-toothed inferior palea ; of 

 this genus there are many species ; A. fatu<i (Wild Oats, or Havers), praten*i* 

 and pu'tescens, are common in cornfields and meadows. The following species 

 are cultivated : A. sativa, the Oat (Fig. 356 A), with its panicles in various 

 planes ; A. oriental^, with its panicles in one plane; A. xtrigo<a, with a hairy 

 floral axis; and A. nuda, the spikelets of which usually consist of three flowers 

 2'risetum (Avna) flavescem, the jellow Oat-Grass, with a free fruit, occurs in 

 pastures. Aira (Deschampsia) ctftpitosa, a,nd.flexuosa, Hair-Grasses, have truncate 

 inferior palese, and are common in meadows and woods. Holcus, the Honey- 

 Grass, has spikelets consisting of two flowers, the upper of which is usually $ 

 and the leaf-sheaths are covered with silky hairs ; it is common in damp meadows. 

 In Arrhenatherum, the False Oat-Grass, the lower of the two flowers is $ . 



Tribe 8. Festiicea : the spikelets are usually many-flowered, and the glumes 

 shorter than the inferior paleae which either have no awn or a straight terminal 

 awn. Melica, the Melic-Grass, has sometimes spikelets consisting of a single 

 flower only : the glumes are long ; it is common in woods. Molinia coerulea has 

 a very long haulm, consisting for the most part of a single internode ; its spike- 

 lets are in loose purplish panicles ; it occurs on moors. Briza, the Quaking- 

 Grass, has spikelets which are compressed laterally and are cordate at the base ; 

 it is common in meadows. Koeleria cristata has dense panicles ; it is common 

 in dry meadows. Dactylis glomerata, the Cock's-foot Grass, has dense panicles 

 divided into parts which have longer stalks ; it is common in meadows. Poo, 

 pratensis, trivialis,ekc. (Meadow- Grass), are common in meadows; their spikelets 

 are compressed laterally ; the glumes have a sharp keel ; P. annua is common 

 by the roadside. Other Meadow-Grasses are Glyceria aqnatica and fluitans, 

 with obtuse unequal glumes, and a lower palea with 5--7 prominent parallel 

 veins, growing in ditches ; and Schlerovhloa maritima, distans, etc., growing in 

 salt marshes and by the sea-shore, with acute unequal glumes. In all the 

 Meadow-Grasses, the fruit is free from the paleas. Festuca elatior, and others, the 

 Fescue Grasses, are common in meadows. Bromus, the Brome-Grass, of which 

 there are several species, is common in fields (B. secalinu*), in meadows (B. 

 raceinonus and others), by the roadside (B. sterilis and mollis). Brachypodium, 

 with shortly-stalked spikelets in a simple raceme, and unequal glumes, is common 

 in woods (B. sylraticum) and on heaths (B. pinnatum). In Phragmites the 

 axis of the spikelet is covered with long silky hairs ; Phragmites communis, the 

 Eeed, occurs abundantly in marshes. Sesleria ccerulea, the Moor-Grass, has 

 laterally compressed spikelets in dense panicles. Gynerium, the Pampas- 

 Grass, also belongs here ; it is dioacious. The upper flowers in the spikelets 

 of plants belonging to this tribe are often unisexual, and <J ; Phragmites is 

 peculiar in that the lower flower of the spikelet is $ . 



Tribe 9. Chluridece : spikelets laterally compressed, usually 1-flowered, sessile, 

 in compound spikes : glumes 2. Cynodon Dactylon, the Dog's-tooth Grass, is 

 often abundant on waste ground. Spartina stiicta occurs in salt-marshes. 



Tribe 10. Hordece : spikelets solitary, or 2 or 3 together, 1- or many-flowered, 

 situated in depressions on the main fl< -ral axis nearly always in two opposite 

 rows, forming the so-called spike: glumes 1-2. In Lolium, the Eye-Grass 

 (L. perenne, Darnel, is common everywhere), the posterior surface (that is, the 

 middle line of the posterior glutne) is directed towards the main axis, and this 



