ECOLOGY OF WOODLAND PLANTS. 381 
The leaves are much narrower and thinner (fig. 35) than in the 
typical form and yellowish green in colour. The cuticle is 
very thin and not corrugated; a single layer of green cells is 
developed beneath each epidermis (fig. 36), chlorophyll granules 
being few and scattered in the remaining cells. A clear rounded 
cell is seen between the vascular bundles, but lacune are not 
developed. The inflorescence, too, is weak, the scape being 
slender and few-flowered, and these are of a pale blue colour. 
Outside the woods the plant nowhere forms extensive masses 
in this area, occurring chiefly on the sites of previous woods and 
hedges and in hedgerows. Here the leaves are much darker in 
colour, broader ard thicker than in the woodland forms (fig. 37). 
The epidermis has a thick lamellated cuticle and is distinctly 
corrugated (fig. 38). Occasionally leaves were found where the 
epidermis was locally two cells deep (fig. 39), the lower ones 
forming a large-celled aqueous hypodermis. The stomata are 
usually deeply sunk. The mesophyll is better developed, with 
fewer air-spaces, and two rows of cells beneath each epidermis 
contain abundant ehlorophyll corpuscles. In the region of the 
midrib the lacune are very large, and occur between the bundles 
on either side up to the fourth or sixth bundle: here the cuticle 
is greatly thickened (fig. 40). 
Leaves collected on April 7th showed the first division of 
cells to form an abciss-layer. This is found just where the leaf 
thickens to form the bulb-scale, aud is easily seen with the naked 
Figs. 41 & 42. 
| 
Fig. 41. Base of leaf of Scilla festalis, showing abciss-layer. 
42. Abciss-layer of Scilla festalis, Longitudinal section. 
eye as a well-defined dark line along which the leaf readily 
breaks (fig. 41). A longitudinal section through the abciss-layer 
is shown in fig. 42. Its development proceeds slowly and is 
accompanied by the decay of the leaf; the first evidence of this 
LINN. JOURN.— BOTANY, VOL. XXXVII. 2E 
