THE NATURAL HISTORY OF BRITISH GRASSES. 15 
present time only a few sorts have been so employed, yet it 
seems desirable so study the habits of grasses more care- 
fully, with a view of increasing this 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, Loliwn perenne (common rye-grass), and 
Lolium perenne, var. Italicwm (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 Loliwm 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 cultiva- 
tion, 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 conse- 
quently dies for the want of living shoots to keep up its 
vitality. Now this is a tendency that increases, 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 acrop the second year. This, 
however, may in a great measure be prevented by early 
cutting 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 xatwral 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 
