1^6 Dr Yule on a Collection of Plants 
As the introduction and naturalisation of useful and or- 
namental plants is an important object of public economy, the 
best means of success forms a question of corresponding inte- 
rest ; especially as it is stated in a late paper, in the Memoirs 
of the Horticultural Society of London, that, of the plants 
sent from China by a person residing in that country for this 
purpose, the proportion of those that survive the passage home 
is on the average about one in 1000 only. 
M. Thouin of the Institute of France, first proposed, with 
this view, sowing the respective seeds in layers, alternating 
with about an inch of earth between them, from the bottom to 
th^ top of boxes fifteen inches deep, and of a convenient size : 
and in this way, he informs us that he has obtained a great 
number of foreign plants in a healthy condition ; but that the 
uppermost layers, germinating early on the voyage, generally 
died*. In Dr Wallich’s present experiment, the same inconve- 
nience occurred. Those seeds only in the undermost part of 
the case were fresh and unaltered, and germinating towards the 
end of the voyage, remained healthy on their arrival here. 
On the whole, from these and similar results, the most pro- 
bable means of success may be deduced. 
1. Repeated disappointment has convinced us, that seeds sent 
home in the usual way generally perish, losing their germinating 
property, from various causes, which it isscarcely possible toobviate 
under the present management. They become either mouldy from 
being excluded from the free atmosphere, when insufficiently dried, 
or, if exposed to a very high temperature, they are entirely exsiccat- 
ed, and the germ, thus deprived of its native moisture, necessarily 
perishes. The seeds of many tribes being preserved fresh, by the 
structureof their husks, and the pulp of their fruits, the necessity of 
preserving these in a sound state, is clearly pointed out by Nature 
herself, instead of the common practice of extracting the seeds and 
imperfectly drying them previous to sending them to Europe. 
2. When we cannot succeed in preserving seeds fresh in 
their original envelopes, and when they belong to tribes whose 
seeds are comparatively naked, it may be presumed in general, 
that these are intended by nature for speedy reproduction ; 
and, in fact, it is difficult to preserve such seeds sound even 
under their native climate ; and, far more so, during a distant 
* Annahii du Miiscum d'Hutoire Natunlle, t. 2. p. 81. 
