472 
The Natural History of Bi-itish Grasses. 
list. For though a number of plants — not grasses — are cultivated 
as " seeds " or " artificial grasses," it is quite unnecessary to 
remark that these are altogether distinct from the true grasses. 
Of the latter, only one species is used to any extent in seeds, 
namely, the Lolium perenne (perennial rye-grass). Of this there 
are several varieties derived from cultivation, the best of which 
is the Italian Rye Grass. Now, these two varieties, namely, 
Lolium. perenne (common rye-grass), and Lolium perenne, var. 
Italicum (Italian rye-grass), possess highly valuable properties ; 
they yield nutritive food, and have an upright mode of growth, 
so that, while adding greatly to the weight of the hay, they 
interfere less than most other species with the surrounding 
herbage ; but as they are now universally grown from cultivated 
seeds, there is in them a tendency to changes which are not for 
the better. This may be shown by attention to the habits of the 
Lolium perenne. In wild nature we see that this grass is entirely 
perennial in habit, hence, in depasturing its green herbage, it 
stools out very considerably ; in cultivation, however, it grows 
straight, upright, coarser culms, which when flowered are cut 
down for hay. It then has a less tendency to " tiller," or " stool," 
and much consequently dies for the want of living shoots to keep 
up its vitality. Now this is a tendency that incieases, and must 
increase, until this plant becomes more of an annual than a 
perennial, and indeed in some districts it is even at present next 
to impossible to get a crop the second year. This, however, 
may in a great measure be prevented by early catting of the 
grass when for hay, and here it is proper to remark that there 
can be no greater injury done to a grass crop, whether natural or 
artificial, than the letting it get too ripe before cutting. 
In all herbaceous vegetation, there is the tendency to die 
wholly, or in part, on the production of seed. Thus annuals die 
at once when they have attained the end of their growth, namely, 
seed for the reproduction of their species, and in many of them 
their duration of life can be delayed for an indefinite period by 
preventing this consummation : thus 1 have made the annual 
Reseda odorafa (mignonette), by constantly pulling off its flower- 
buds, groAV for three years, and assume the form of a woody 
plant, dying, however, on the fourth year, on their being allowed 
to seed. 
In October, 1849, I planted a patch of wheat in one of my 
experimental plots of five yards square; this I kept constantly 
cut down during the summer of 1850, and it stood the winter of 
1850-51, and became a tolerable crop in the summer of 1851, 
thougli much of it had died in the mean time. Oats and barley 
treated the same quite died out. 
Now, these experiments show, that not allowing seeding indue 
