28G Mr. Burnett on the Adumbrations 



an entire plant, so as to remind one of the primitive ubiquity 

 of root ; when, as in the protophytes, the nutritive and repro- 

 ductive organs were mutually and indistinguishably blended 

 with each other, forming but one common yet effective whole. 



It is matter of notoriety that plants, even what we consider 

 the more perfect kinds, derive nourishment from the atmos- 

 phere as well as from the soil ; and this in very different 

 degrees : that some depend much on this, some much on that; 

 and again, in others it is directly the reverse ; that some 

 plants will flourish on very poor soils, and others wane in 

 comparatively good ones ; that thistles will grow and enrich 

 a plot where corn would degenerate and die. The turnep 

 husbandry has practically familiarized this to every one, and 

 the farmer well esteems the rest, to say the least of it, if not 

 improvement, which such a crop affords to land, while wheat 

 impoverishes it greatly. Experiments have proved that plants, 

 with few and small leaves, depend almost entirely on the re- 

 sources of the soil, those with many and large ones almost as 

 exclusively on the atmosphere around them ; the mosses, and 

 most of the pseudo-parasites, for example : and some of the 

 Epidendra, as the Flos aeris, will grow while hanging from 

 the boughs of trees into which no roots are sent, or even, if 

 suspended by a cord from the cieling of a room, will produce 

 leaves and flowers for months or years together, nourished 

 only by the elastics floating in the air. In some of the simpler 

 tribes, the stem or entire plant, and in others, both sides of 

 the leaves, or leafy appendages, equally absorb nutriment from 

 the water or the air ; others absorb chiefly or only by a single 

 surface, which sometimes is the under, sometimes the upper 

 page; and when, as in the connate leaves of Dipsacus, the 

 hollowed basin of Hydrocotyle, or the follicular appendages 

 of some rare plants in which a sac is formed by the intorsion 

 and coadunation of their leaves, in which water and other 

 matters are not only lodged and retained, but can be thence 

 absorbed by the vessels of the plants which are spread therein, 

 a considerable advance has been made in these pouch-like 

 reservoirs towards an internal cavity for the reception and 

 retention of food. 



In many plants, in which concavities are found of various 



