COMPARISON OF THE SELANTHI WITH 6THER PLANTS. 
61 
disappeared; although, while they are in growth, the strong 
action parches the ground, and makes the common herbage dis¬ 
appear. Humidity is essential to their vigorous action; and 
after a rainy night, numbers of them may be found in the morn¬ 
ing, where not one was visible on the preceding day. This shows 
that a solution in water of vegetable matter, while in a state of 
decomposition, is essential to the vigorous action of the fungi ; 
and this is confirmed by the fact, that, in places and years of 
showery autumns, they are far more abundant than when the 
autumn is dry. 
Drought is the autumn and the winter of vegetation in tropical 
climates, and in all climates approaching to a tropical character; 
and, therefore, such climates are by no means adapted to the 
natural habits of the fungi. The Selanthi come, in part at least, 
to perform in tropical latitudes the office which is performed by 
the fungi in latitudes of more polar character ; and though we 
know but little of their physiology, analogy leads us to conclude 
that they receive the products of decomposed vegetable matter 
through the medium of air, rather than that of water. Thus we 
may, without impropriety, style them a sort of air fungi; and as 
their mode of action is different from that of the fungi properly 
so called, so also is their organization. The genuine water- 
plants, or those that grow wholly in the water, or are only par¬ 
tially exposed to the free atmosphere on the ebbing of the tide, 
have no flowers in the common meaning of the term; and the 
fungi, at least in what are considered the essential parts of a 
flower, agree with them in this respect. The Selanthi also agree 
with the fungi in some parts of their structure, and in several of 
their properties ; but, in others, they agree with flowering-plants. 
We need hardly mention, that the grand division, as regards their 
texture, of plants, is into those which are cellular, or wholly made 
up of membrane, forming a tissue of cells of some form or other ; 
and vascular, or those which have their cellular tissue more or less 
interspersed with tubular vessels. The first of these divisions 
consists of plants which, though they have organs of fructification, 
have no flowers, according to the common definition ; and though 
they perfect spores, or germs, often in numbers almost incredible, 
those germs have in no case the same organic structure as the 
true seeds of plants with ordinary flowers. The vascular plants, 
again, all have flowers ; in which the fertilizing and fertilizable 
