OF THE LEAVES OF BRITISH GRASSES. 347 
Part II. 
There remains to be considered the structure of grass-leaves from the point of view of 
their arrangement in groups according to habitat; to try to discover how far the leaf- 
structure is constant throughout an ecological group; and, if possible, to explain the 
characteristic leaf-structure of the grasses of a groupas an adaptation to the environment, 
and to account for the exceptions. For this purpose I have divided the grasses whose 
leaf-structure I have examined into seven groups, as follows :— 
i. Grasses of Meadows and Pastures. 
li. e Waste and Sandy Places. 
iii. »" Woods and Shaded Places. 
iv. is Maritime Sands. 
v. A Moors and Heaths. 
vi. » Wet Places. 
vii. Alpine Grasses. 
The distinctions between these groups are not very definite, and in nearly every group 
I have had to include grasses which might equally well, possibly better, have been 
included in one or other of the remaining groups. 
In what follows, when speaking of a leaf-structure as typical, I merely mean to 
imply that this leaf-structure appears to me to be that which is best adapted to its 
environment. 
i. Grasses of Meadows and Pastures. 
Grass. Duration. Figure. 
Festuca duriuscula |. Perennial. 17 
rubr, 8. $^ idYnWeevwod, sed s » 7 
Hae iru LLL E cs T4 Doi d J 50. 
SUREMEE 4 o uc. prs ue oo. rd » — 
a, STEM Ca 0.4 ou 3 9 uos os e 46 
e e get TT CEN S » 18 
Anthozanthum odoratum . . . e e . . . » — 
DUM) Gime aa det et et Gi Af UC » T 
POO mahs "` LT VON ou uo DAVIS WW — 
PUNR colo XO. E SRI S » P 
Bre meld o0 ciue ox VI uus vue *) a - 
Arrhenatherum avenaceum . >. o s o » v 
Lohun PORN g E e e o4 Li D Lë 
EE S o. a oe. EE » 24 
Horde proteinë s so ron ane oS e S T D 40 
ROGGE ATURE a or eo M ” 15 
Bt, V S007? CUM PE s » pus. 
DUE TC Uy M S Eë ues » E 
CHE pinia > Ee ENG 3007 A » 10 
Hierotblos boreala our ware e ue i cos j 30 
Oynorurus crUlali o a sois o on ont uet ote » ym 
pia Caan V. . € B os oe o n UM "s 20 
JUNE valence t n » 38 
3D 
. SECOND SERIES.— BOTANY, VOL. VI. 
