THE VITALITY AND DISTRIBUTION OF SEEDS 
299 
The seedlings have been weeded out each year, never being allowed to 
flower. The garden is not double-trenched, but is simply dug over 
superficially; Ulex seeds are too large to be transported by winds and 
are not known to be carried by birds. Upon considering this case in 
connection with recent researches we must first note that seeds of 
some Leguminosae may retain their vitality for fifty years or longer; 
therefore, assuming that Jjlex seeds have sufficiently hard coats, there 
is no reason why they should not continue to germinate in this garden 
for another quarter of a century, or even longer. Probably each year 
a certain number of the seeds which may have been deeply buried by 
the action of worms, rains, etc., have been brought to the surface by 
the fork or other agency. It would be interesting to double-trench a 
small portion of the area, in order to discover whether the number of 
seedlings following the operation is greatly increased in number. 
Ulex shoots it seeds a considerable distance, so probably we should 
find upon enquiry that the area covered by these seedlings is rather 
wide. 
Some twenty years ago I was told by the occupier of the Bell Farm, 
Stan way, Colchester, that his garden had been double-trenched 
about once in five years for a long period of time; and that invariably, 
after the double-trenching, a great crop of Adonis autumnalis 
appeared. The plant gradually died off, but the crop again appeared 
after the next double-trenching. I visited the garden a year or two 
after a crop had appeared, and noticed that there were still a few 
specimens of Adonis scattered about. This occurrence appears to be 
consistent with the results of recent researches. The soil is naturally 
replenished with seeds every five years, a period which does not appear 
to be unduly long for seeds of wild plants to retain their vitality 
when self-buried under natural conditions. 
About the same time I had an interesting conversation with a 
seed-grower at Colchester, who pointed to a seed-bed in which an 
alien plant of Tropceolmn majus had appeared. (Seed-growers, of 
course, carefully exterminate any alien which appears in their seed¬ 
beds.) He said that it was strange that the seeds of Tropceolum 
majus , which lose their vitality very rapidly in seedsmen’s packets 
(after two years P), should continue to appear in the seed-bed for at 
least seven years after a crop of Tropceolum had been harvested. 
This observation appears to suggest that if Duvel had planted his 
cultivated and wild seeds in suitable soil, and under the natural 
conditions of self-planted seeds, he might have found the vitality of 
some of his seeds to be considerably prolonged. This indicates a line 
of research which might give important results. One would suggest 
the planting of seeds of both cultivated and wild species, under con¬ 
ditions approximating as closely as possible to Nature and in soil of 
the character preferred by the species, all seedlings being destroyed 
yearly as they appear. The length of vitality of different seeds in 
Nature could thus be determined with some accuracy. 
How ancient many of our species are has been demonstrated by 
the work of Clement Reid on the seeds of geological strata ( The 
Origin of the British Flora , 1899). His researches brought to our 
