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MESSRS. J. B. LAWES, J. H. GILBERT, AND M. T. MASTERS, 
by external conditions. Referring the reader to his paper* for full details, it may 
here be stated on his authority, that the hard woody fibres beneath the epidermis of 
the leaves ol grasses—“the hypodermic fibres”—which form a protecting sheath to 
the fibrovascular bundles of which they are indeed a dependence, and which must 
greatly contribute to the rigidity of the leaf, are fostered in their growth in hot dry 
situations. Shade and moisture, on the contrary, are not favourable to their development. 
It is easy to see the bearing of these facts on the question of the struggle for existence. 
Speaking of the cellular or parenchymatous structure of the leaves of grasses the same 
botanist remarks that there are, speaking generally, three categories of cells : 1, those 
with green chlorophyll; 2, colorless cells without chlorophyll; 3, stelliform cells. The 
green cells predominate in grasses growing in cool shady localities ; the colorless cells 
are relatively abundant in species growing on sandy sea-coasts ; while the stelliform 
cells are especially abundant in aquatic species. 
Flowers , &e. —It forms no part of our purpose to describe in detail the inflorescence 
or the floral structure of such well known plants as those which constitute the mixed 
herbage of the plots. A few general observations may, however, appropriately be made 
in illustration of the competition that is goingon between them. Some of the plants 
on the plots never get an opportunity of flowering; others flower, but do not perfect 
their seed before they are cut by the scythe. It might be expected that the duration 
of such plants would be prolonged, as the flowering, and still more the seeding, is so 
exhausting to the plant. Some plants which do not get an opportunity of flowering 
or seeding before the first crop is cut, do so before the aftermath is taken. The 
early or late flowering is, therefore, an element to be considered. 
Other matters relating to fertilisation, such as the question whether particular 
flowers are self-fertilised or fecundated by wind-wafted pollen, or by pollen carried by 
insects, are amply deserving of study, with special reference to the advantage or 
injury resulting to some of the competing plants by such complex interactions.! For 
instance, if in any given season the particular insects adapted to fertilise any parti¬ 
cular flower were from any cause absent, or present in diminished numbers, the 
number of seedlings of that plant would be proportionately diminished, and vice versa. 
Some plants, again, like Rumex Acetosa, seed more abundantly than others. This 
is a dioecious, wind-fertilised flower, whose seeds are dispersed in abundance, and as 
* 1 Ann. Sc. Nat. (Botanique),’ 1875, yoI. 1, p. 367. [See Yesqub in the same publication, vol. xiii., 
1882, p. 24, and Stahl as quoted by Yesque ; also Hackee’s ‘Monograph of European Fescues,’ of which 
an abstract is given in Trimen’s 4 Journal of Botany,’ September and October, 1882.] 
f With reference to the “ relation of organism to organism, the most important of all relations,” see 
Darwin, ‘ Origin of Species,’ chapter 3, and as to the relative advantages to the species of self or of 
cross-fertilisation, see Darwin ‘ On the Effects of Cross and Self-Fertilisation in the Yegetable Kingdom,’ 
and on ‘ The Different Forms of Flowers on Plants on the same Species.’ As to the fertilisation of grasses, 
see Bidard, Comptes Rendus, 1869, p. 1486 ; Syme, in ‘ Journal of Botany,’ 1871, p. 173, and in ‘ Journal 
of the Royal Horticultural Society,’ 1872, vol. iii., p. 7; Spruce in same publication, 1872, vol. iii., p. 4; 
A. S. Wilson, ‘ Gardeners’ Chronicle’, March 14, 1874. 
