456 
MR. A. J. EWART ON ASSIMILATORY INHIBITION. 
No evolution of 
Oxygen. 
Weak but distinct 
Assimilation. 
Moderately to fairly 
active Assimilation. 
Assimilation quite | 
active. | 
Ozalis Ace-| Pale yellowish green: 
tosella. 
Leaves de- 
veloping 
on last 
year's rhi- 
zomes. 
Phaseolus 
vulgaris, 
Chlorophyll grains 
less than 1 normal 
size. P. Ir. Leaf- 
lets, L. Ys; B. yo. 
Yellowish green. 
Folded leaflets, 
L.i; B. }. Par- 
tially expanded 
leaflets, L. ys; 
B. To 
As before, but chlo- 
rophyll grains } 
to 1 normal size. 
P. X. Leaflets, 
L. 4; B.i: 
Leaflets expanded 
and faintly yel- 
lowish. Chloro- 
phyll grains small, 
but abundant and 
green. L. i; B.1. 
Leaflets still folded | Leaflets partly ex- | 
and yellowish green. 
Chlorophyll grains 
1tol; P.r. Leaf- 
lets, L. 4; B. 1. 
Quite green *. L. 1; 
B. 4 (largest ter- 
minal leaflet). 
| 
panded and quite | 
green. Chloro- | 
phyll grains 3 to 
1, P. š. Leaf- 
lets, L. 1; B. 1. 
Leafiets. 
B. 3. 
L. 3; 
* At this stage in the development of the leaf its green colour is darkest: 
This is owing to the greater transparency of the young leaf, and not to any 
real greater intensity of coloration. 
The adult leaf, owing to the development 
of air-spaces in the mesophyll, becomes less transparent and of a lighter green 
tint. 
Marchantia polymorpha.—Gemme, average adult diameter (D.) 1mm. D. 3. 
Quite active evolution of oxygen. D. 4$. Chlorophyll grains very small, 
but gemme green ; distinct but much weaker assimilation. 
200 cells). Chlorophyll grains extremely small. 
less, centre yellowish green, and here just perceptible trace of evolution 
of oxygen. D.s. Central part distinctly greenish, but no evolution of 
oxygen. 
Bryum cespititium.— Length of leaf 3 adult size. 
normal size and slightly yellowish, but assimilation quite active. 
Chlorophyll grains smaller and smaller from apex to base of leaf. Apical £ 
fairly active assimilation, middle } weak, 
but distinct evolution of oxygen in apical 4 of leaf only. L. 8. Noevo- 
Chlorophyll grains distinet and yellowish green in 
lution of oxygen. 
apical portion of leaf, but in basal part almost colourless. 
Dicranum scoparium.—L. 4. Quite active assimilation. 
assimilation ; basal part, chlorophyll grains smaller and weak assimilation. 
L. y. Protoplasm reticulate and transparent. 
basal à none. 
D. 15 (100- 
Margin almost colour- 
Chlorophyll grains about 
L. 1, Weak 
L. }. Fairly active 
Apical half, chlorophyll 
11 
“20° 
grains nearly normal size, moderately active assimilation ; basal half, chlo- 
rophyll grains much smaller, assimilation quite weak. L.1. Apical portion, 
chlorophyll grains fairly large and green, very faint assinnlation ; basal 
half, chlorophyll grains smaller and smaller, at extreme base almost 
colourless, no evolution of oxygen. L. X. No evolution of oxygen. 
Chloropbyll grains in apical portion yellowish green, and, though small, 
larger than in base of leaf, L. 5, where a weak assimilation is shown. 
