166 MONOCOTYLEDONS. GRAMINE.'E. MellCCt. 



1. H. avenaceuS) perfect floret superior scarcely awned, imperfect 

 one antheriferous with a very long jointed awn, root knotted, 

 p. 28. Pastures. 



2. H. mollis, perfect floret inferior and awnless, imperfect one 

 antheriferous with a bent awn reaching beyond the glume, root 

 creeping, p. 28. Hedges and pastures. 



3. H. lanatus, perfect floret inferior and awnless, imperfect one 

 antheriferous with a curved awn included in the glume, root 

 fibrous, p. 28.< Pastures. 



14. AIRA. 



Glume 2-valved, unequal, 2-flowered. Perianth 2-valved, the 

 outer one awned above the base (rarely awnless). Florets with- 

 out any imperfect ones between them. Caryopsis free, but co- 

 vered with the perianth. 



* Perianth awnless. 



1. A. cristata, panicle spiked, florets longer than the acuminated 

 glumes, leaves hairy, p, 29, Dry pastures, near the sea. 



2. A. aquatica, panicle spreading, glumes obtuse, florets longer 

 than the glumes, p. 29. Watery places,. 



** Perianth awned. 



3. A. ccespitosa, panicle diffuse, branches scabrous, florets villous 

 at the base rather longer than the glume, awn straight inserted 

 near the base of and not exceeding the perianth, leaves plane, 

 p. 29. Shady places. 



4. A. alpina, panicle subcoarctate, branches and pedicels perfectly 

 smooth, florets villous at the base as long as the glume, awn 

 inserted above the middle of and scarcely exceeding the peri- 

 anth, leaves linear, p. 30. Alps. 



5. A.Jlexuosa, panicle (when flowering) diffuse, florets villous at 

 the base as long as the glume, awn jointed inserted near the 

 base much longer than the perianth, leaves setaceous, p. 30. 

 Heaths. 



6. A. caryophyllea, panicle divaricate, florets scarcely villous at 

 the base shorter than the glume, awn inserted below the middle 

 jointed longer than the glume, leaves setaceous, p. 30. Dry 

 pastures. 



7. A. prcecox, panicle somewhat spiked, florets scarcely villous at 

 the base about as long as the glume, awn twisted inserted be- 

 low the middle longer than the glume, leaves setaceous, p. 30. 

 Sandy pastures. 



15. MELICA. 



Glume 2-valved, about 2-flowered, with the rudiment of a third 

 floret. Perianth 2-valved, awnless. Caryopsis free, covered 

 by the cartilaginous perianth. 



