TABLE Oil- 
Dimension! of leaf. The black lines i n co l nia |,„d 4 indicate the position of the mid-rib. 
Species of 
Bromus. 
(1) 
Width 
leaf : 
direct 
measure- 
ment. 
(2) 
No. 
°f 
ribs. 
(3) 
Distances between the ribs measured from axis 
direct ( low power). 
axis 
(4) 
,„ CK between ribs measured on transverse 
sections of leaf. 
(5) 
Average 
total 
breadth 
of ribs 
(sections). 
(6) 
Depth of 
mid- rib. 
(7) 
Depth 
at 
Sinus. 
(8) (9) 
Mean sectional 
area of chloro- 
phyll tissue per 
mm. of breadth. 
Margin 
to No. 1 
1-2 
2-3 
3-4 
4-5 
5-6 
6-7 
No. 7 to 
margin. 
Total fji. 
ft 
J 2-3 
3-4 
4-5 
5-6 
6-7 
No. 7 to 
margin. 
Total p. 
B. mollis 
1*2 mm. 
3 
19a 
39° 
4° 2 
210 
JI 94 
*95 
5I423 
188 
1241 
237 
260 
*5° 
Iio 
88,990 
B. tectorum 
i-7 
5 
162 
358 
358 
312 
325 
r 43 
i6 57 
234 
9 455 
435 
423 
324 
2300 
224 
325 
152 
238 
214,200 
B. ciliatus 
1.8 
5 
169 
357 
390 
325 
325 
Hi 
1709 
227 
2 423 
429 
422 
140 
2083 
224 
260 
130 
195 
1 74»°3° 
B. brizaeformis 
2.0 
5 
162 
325 
338 
345 
338 
I 75 
1683 
>95 
■5 337 
337 
345 
162 
1720 
198 
260 
127 
193 
171,770 
B. secalinns 
3.4 
5 
260 
455 
455 
455 
455 
260 
2340 
247 
'5 4® 1 
448 
442 
241 
23H 
300 
325 
151 
238 
207,060 
B. macrostachys 
1.9 
5 
221 
357 
39° 
390 
325 
T 95 
1878 
■95 
'5 325 
325 
325 
195 
1710 
210 
293 
146 
219 
192,063 
B. pratensis 
B. inermis 
1*2 
5 
143 
293 
292 
292 
293 
98 
1411 
163 
'8 305 
3ii 
305 
182 
1584 
218 
260 
.”7 
188 
155,358 
B. velutinus 
2.0 
5 
227 
39° 
39° 
39i 
39° 
227 
2015 
280 
55 4t>9 
39° 
39° 
260 
2184 
236 
342 
i33 
237 
201,190 
B. sterilis 
2*0 
5 
228 
377 
35i 
325 
364 
195 
1840 
260 
35 423 
468 
455 
253 
2294 
243 
293 
101 
J 97 
176,315 
B. maximus 
3*° 
7 
195 
325 
520 
520 1 
I520 
520 
39° 
169 
3159 
195 4 
10 520 
520 
I520 
5°7 
338 
182 
3192 
410 
325 
147 
236 
205,685 
B. madritensis 
S 
182 
338 
325 
325 
35i 
169 
1690 
195 3 
25 3°5 
1 325 
325 
i95 
1670 
192 
214 
120 
203 
i79>655 
B. Schraderi 
2-1 
7 
130 
292 
325 
325 
325 
325 
260 
130 
2112 
130 2 
80 312 
325 
338 
292 
260 
130 
2067 
333 
188 
100 
144 
120,808 
B. unioloides 
2*5 
7 
162 
293 
338 
332 
326 
39° 
299 
163 
2303 
195 
5i 39° 
4°3 
39° 
39° 
325 
162 
2606 
327 
260 
149 
204 
178,402 
B. racemosus 
i-75 
5 
196 
365 
33° 
33° 
360 
220 
1801 
307 
90 37i 
345 
384 
262 
2059 
249 
288 
120 
204 
i79,3i6 
B. commutatus 
1.1 
3 
160 
416 
420 
190 
1186 
185 j 
'4° 350 
160 
i°35 
134 
224 
109 
166 
144,420 
B. interrnptus 
1.0 
3 
160 
37i 
352 
160 
1043 
204 
P 439 
198 
1263 
147 
268 
122 
i95 
172,303 
B. arvensis 
1.2 
3 
192 
360 
384 
172 
1108 
198 
l 8 4 37 i 
192 
ii45 
134 
262 
96 
179 
155,857 
B. canadensis 
i-7 
5 
!95 
325 
325 
325 
325 
162 
1657 
208 
!«4 312 
306 
312 
195 
1697 
269 
273 
162 
2X7 
182,497 
Ann. Bot. } Vol . XVI. To face p. 307.] 
1 
