14 
Ridley .— The Distribution of Plants . 
abundant there. Sowerby reports it as having been introduced into 
England as an ornamental annual in 1796, and I have seen a specimen, 
probably cultivated, from Chelsea in 1802. In other parts of the world 
the earliest dates I have procured are Peru, 1806 ; North America, 
apparently wild, 1893; India, 1845; Java, 1899; New Zealand, 1894; 
Africa, 1912. 
Galinsoga possesses fruits with broad scales forming a pappus, and 
thus has a superior method of dispersal to those of the Matricaria , which 
possesses no scales or plumes at all on the achenes. 
Matricaria discoidea , DC. (M. suaveolens , Buch.), is a much smaller, 
inconspicuous weed with small and light fruits quite unprovided with any 
particular means of dispersal. When ripe they become detached from 
the receptacle and are partially covered by the involucral bracts which 
curl over them. The plant is only about four to six inches tall. Hold¬ 
ing the achenes on my hand, about two feet from the ground, I find 
that in a strong wind they are blown three or four yards before falling 
to the ground. At the normal height of the plant they would not, of course, 
travel so far. 
The plant’s first record in England that I can find is 1878, Kew 
(Druce), but I find specimens from Berlin, 1853 5 Konigsberg, 1862 ; 
Dorpat, 1869. It now occurs on roadsides and paths all over England, 
from Surrey and Berkshire to Aberdeen, and probably farther, and is 
abundant everywhere. 
Now here are two weeds, one of which ( Galinsoga :) has been over 
, a century in the country, and though very abundant locally has not yet 
migrated more than a few miles from the spot in which it was first intro¬ 
duced, and another, the Matricaria , with poorer facilities for seed-dispersal, 
has in less than half a century spread over the whole of England and Scotland. 
It is quite clear that in these cases the age of duration or time in which 
the two plants have been in the country is not commensurate with the 
extent of their distribution. The spread of the later introduction has been 
more rapid and wide than that of the earlier one. 
Widely distributed Plants. 
I intend in this section to deal mainly with Phanerogamous plants, but 
will make a few remarks about Cryptogams first, chiefly illustrating by 
Malayan species. 
We know little at present about the cellular plants of the Malay 
Peninsula, as they have been little collected and still less worked out. 
They are, on the whole, much more widely distributed than flowering 
plants, or rather there are more widely distributed kinds than there are 
of flowering plants. This would give some colour to Dr. Willis’s theory 
