48 MISSOURI BOTANICAL GARDEN BULLETIN 
the seed once get hard by being removed from the water, 
it is almost impossible to break it, so that years may pass 
without germination unless the coat has been scratched or 
filed. When this is done, however, and moisture admitted, 
they will germinate within 24 hours. The value to the plant 
of such a seed is that, should the pond in which it is growing 
dry up and the seed fail to fall into water, it ean lie dormant 
awaiting a return to its natural aquatie habitat. It is inter- 
esting to note in this connection that seed of Nelumbium 
have retained their vitality for the longest period authentically 
determined thus far. Robert Brown, an English botanist of 
the early part of the nineteenth century, records that seeds 
of Nelumbium were sent by Sloan to the botanical department 
of the British Museum. A hundred and fifty years after- 
wards he found them in the original boxes in which they 
had been transmitted. Brown himself succeeded in germinat- 
ing these seed, and there seems no reason to doubt the accuracy 
of his account. At the present time this stands as the record 
for the longevity of seed, and, owing to the nature of the 
Nelumbium seed, it is reasonable to suppose that they might 
retain their viability for such a period. However, in the 
case of wheat and similar seed supposed to have lived thou- 
sands of years, no credence is to be attached to the sensational 
assertions as to their longevity. 
PLANT IMMIGRANTS OF OUR LOCAL FLORA 
As most plants lack independent means of locomotion, their 
dissemination is dependent upon outside agents. Many plants 
owe their wide distribution to water fowl whose habit of migra- 
tion permits them to carry seeds in earth on their feet or in 
their plumage. Plants, such as currants, gooseberries, apples, 
ete., whose seeds are enclosed in edible areas and are pro- 
tected by hard coats permitting them to pass through the 
bodies of animals without injury, are often carried long dis- 
tances, and if deposited in favorable locations for growth 
soon start independent colonies. Migrating mammals aid in 
the distribution of such plants as burdock, tick trefoil, and 
beggar’s lice, the seeds being provided with prongs or hooks 
which become attached to the furs of the animals. Other 
plants whose seeds possess tufts of fine feathery hairs, such 
as dandelions, thistles, and asters, are widely distributed by 
wind currents, as are also plants of the tumbling habit, in 
