1870. | | in Natural Selection in Plants. 413 
sidered, has been inferentially if not directly shown, where the 
effect of an unusually wet season is referred to; so certain plants 
which now dominate in my immediate neighborhood illustrate 
how natural selection has assisted, to say the least, in producing 
the change in the open fields near my residence in Berkeley, 
through the advantage which one form of seed has over seeds of 
a different form. And this aside from its interest to the scientific 
observer, is of special interest to the farmer, for it enters into the 
economics of his business, as may be seen further on. 
Only a few years ago the entire region hereabout, from the hills 
to the shore of the bay, was either farmed or used for pasturage. 
Where not tilled, over large portions of this area, the wild mus- 
tard (Brassica nigra) abounded, and was regarded by the farmers 
as a pest; it grew and thrived nearly everywhere, and often 
attained a height sufficient “to hide all of a standing horse but 
his head.” During later years the mustard has surrendered a 
part of the field to an (introduced?) turnip and radish, plants of 
the same order, with smooth seeds, and all three of thesé have 
been giving way, gradually yielding to other plants, native and 
introduced. 
The mustard may, in some localities, regain in part its lost 
supremacy, through the assistance of man, as the seed within a few 
years has become of economic importance, and is now prepared 
for culinary purposes, and is also on the list of products in the 
export trade of the State.! 
The principal plants within the more limited area first men- 
tioned in this paper, to which these smooth-seeded Crucifere have 
been gradually yielding, have seeds of a different form. One of 
these is the A/fil/arilla, or “ filaree,’ by which name it is more 
generally known, a plant which is closely related to the gerani- 
ums, if we may judge from analogies of form in leaf and flower, 
structure of seed receptacle and shape of seeds. This alfillarilla, : 
as it is called by the Spanish Californians, is an Ærodium, and two — 
species grow here, namely, £. cicutarium and E. : moschatum? 
- UIn 1875, 1013 centals, valued at $4849; 1876, 5458 centals, valued at $18,314; 
1877, 5065 centals, valued at $15,412, and in 1878, 7552 centals, valued at $21,689, 
were exported to foreign countries, making a total for the four years of 19,088 cen- 
tals of the value of $60,264. 
? Cattle eat these readily and appear to be fond of them, but the latter ices espe- 
cially is nota oo plant for milch cows, as it gives a 
taste to the 
