ON EPIDERMAL CHLOROPHYLL. 859 
in mind.* Speaking generally, the latter cells’ chlorophyll is 
markedly deeper in shade than is that of the epidermis. In size 
the epidermal grains are almost always much smaller than those of 
the other cells; but they are usually about as large as the stomatal 
guard-cell grains, though considerably larger in Solanum (tuberosum, 
nigrum, Dulcamara); in Petunia nyctaginiflora ; in some Composite, 
as Arctium Lappa and Lactuca sativa; and in Polygala vulgaris, 
Melampyrum pratense, Urtica urens, Mercurialis annua, Bryonia 
dioica, &e. 
In the matter of the — to both upper and lower leaf- 
epidermis, I differ almost as widely from Stéhr as he does from old 
authors upon the general question: According to him, only 12 of 
the 102 types had chlorophyll i in their upper and lower ee 
as many as 26 out of 50 examined by me were in this condition, viz. :— 
cabsies 
a annua. 
Jrtica urens. 
Nigella damascena. Dahlia sp. 
Capsella ving: gi ri Senecio vulgaris 
ole odor; Chrysanthemum ‘Leucanthemum 
V. canina. Pyrethrum sinense. 
Bhat odorata. Tagetes patula. 
a eptbus barbatus. Centaurea Cyanus. 
Stellaria media. C a um. 
Pelargonium zonale. Rhododendron ponticum. 
Ribes nigrum. Petunia nyctaginiflora. 
- rubrum. Solanum Dulcamara. 
Cirewa lutetiana. + i 
1 
Cucurbita ovifera. 
Bellis perennis. 
The remaining 24 had chlorophyll only in the lower epidermis :— 
Sisymbrium officinale. Petroselinum sativum. 
Arabis alpina. Lactuca sativa. 
Mahonia aquifolia. Chrysanthemum frutescens. 
Hibiscus africanus. Anagallis arvensis 
Oxalis Acetosella. Primula vulgaris. 
prepeelae majus. Digitalis purpurea. 
Borrago officinalis. 
ee Oxyacantha. Lamium purpureum. 
Fragaria elatior. Mentha piperita. 
Ribes Grossularia. Verbena chamedrifolia. 
Godetia rubicunda. Spinacia oleracea. 
Bryonia dioica. 
Of the first list, Nigella damascena, Viola odorata, Pelargonium 
zonale, and Ribes rubrum are said by Stéhr to have chlorophyll on 
the under-side alone, but careful re-examination has confirmed my 
former opinion with respect to these. Nigella damascena is remark- 
able for having spaces of epidermis without chlorophyll alternating 
with chlorophylligerous ones. 
* In a few cases plasmolysis was practised ; usually this is quite unnecessary. 
