76 TRIANDRIA DIGYMA. [CL. IIT. 



with green ribs, smooth : husks minutely wrinkled. Annual : flowers in 

 July and August : grows in corn-fields about London and Norwich : 

 rare. Eng. Bot. vol. xiii. pi. 874. Eng. Ft. vol. i. p. 98. 125. 



2. P. viride. Green Panick-grass. Panicle spiked, cylindrical, con- 

 tinuous, with numerous prominent bristles, rough, with erect teeth 



Smaller than the last, but closely resembling it, the principal differ- 

 ence lying in the more numerous bristles with teeth directed upwards. 

 Annual : flowers in July and August : grows in sandy fields about 

 London and Norwich : rare. Eng. Bot. vol. xiii. pi. 875. Eng. Fl. 

 vol. i. p. 99. 126. 



3. P. Crus-galli. Loose Panick-grass. Panicle erect, branched, 

 bristly; flowers awned, unilateral; leaves lance-shaped, harsh, destitute 



of stipules. Root fibrous : stems about a foot high, smooth : leaves 



pointed : panicle erect, stiff, unilateral, with angular rough-edged stalks. 

 Annual : flowers in July and August : grows in wet corn-fields near 

 London : rare. Neither this species nor the two preceding are indigenous, 

 having been introduced among corn. Eng. Bot. vol. xiii. pi. 876. Ing. 

 Fl. vol. i. p. 100. 127. 



23. Al'RA. HAIB-GRASS. 



Calyx of two unequal, keeled chaff-scales, containing two per- 

 fect flowers, without rudiments of a third. Corolla of two oblong, 

 unequal husks, the outer larger, generally with a twisted awn 

 arising from above the base, the inner notched and awnless. 

 Nectary a cleft scale. Filaments hair-like; anthers protruded, 

 pendulous, notched at both ends. Germen egg-shaped. Styles 

 short, distinct ; stigma large, feathery. Seed egg-shaped, loose, 

 covered with the membranous husks. Named from airo, to de- 

 stroy, formerly applied to Lolium temulentum. 39. 



* Corolla awnless. 



1. A. cristdta. Crested Hair-grass. Panicle dense; calyr longer 

 than its stalk, shorter than the flowers ; chaff-scales and husks pointed. 



Root in dense tufts with downy fibres : stems erect, about nine 



inches high : panicle close, lance-shaped, with silvery, purplish, erect 

 flowers. Perennial : flowers in July and August : grows in dry pastures : 

 common. Eng. Bot. vol. ix. pi. 648. Eng. Fl. vol. i. p. 101. 128. 



2. A. aqudtica. Water Hair-grass, Panicle spreading ; flowers awn- 

 less, even, obtuse, longer than the calyx ; leaves flat ; stipule oblong. 



Root creeping : stems floating, branched, smooth, rising about a 



foot above the water : panicle erect, with spreading branches. Peren- 

 nial : flowers in June : grows in ditches, pools, and the edges of rivers : 

 not uncommon. Eng. Bot. vol. xxii. pi. 1557. Eng. Ft. vol. i. p. 102. 



129. 

 ** Corolla auned. 



3. A. cKspltosa. Turfy Hair-grass. Panicle spreading ; flowers about 

 the length of the calyx, abrupt, hairy at the base ; awn short, from the 



lower part of the outer husk; leaves flat. Straws from two to four 



feet high, erect, smooth, growing in large tufts : panicle large, much 

 branched, with small silvery purplish flowers. Perennial : flowers in 

 June and July: grows in moist shady places, and in alpine ravines: 

 common. Eng. Bot. vol. xxi. pi. 1453. Eng. Fl. vol. i. p. 102. 130. 



