VEGETABLE AND ANIMAL LIFE. 



97 



ciously, as does also the ostrich, which is in consequence said by the Arabs 

 never to drink. And yet these are animals almost as succulent as any we 

 are acquainted with. 



But however true this may be with regard to animals, we have manifest 

 proofs that vegetables of certain tribes and descriptions are altogether sup- 

 ported by the atmosphere that surrounds them ; for, important as is the 

 organ of a root to plants in generai, there are several which have no root 

 whatever, and can derive nutriment in no other way. The water-caltrop* 

 is an instance directly in point. The seed of this plant has no rostel, and 

 consequently can never, in the first instance^, become rooted. From the 

 horned nut or pericarp of the seed, as it lies in water, which is its natural 

 element, shoots forth a long plumule perpendicularly towards the surface 

 of the stream ; during the ascent of which a variety of capillary branched 

 leaves shoot forth from the sides of the plumule, some of which bend down- 

 ward, and fix the whole plant to the bottom by penetrating into the soil be- 

 low the stream ; the leaves alone in this late stage of germination acting the 

 part of a root, and giving maturity to the still unfinished plant. The cac- 

 tus genus, in some of its very numerous species, offers us an example of 

 similar evolution ; and especially in the opuntia tribe, or that which em- 

 braces the prickly pears or Indian figs of our green-houses, of which the 

 cochineal plantj is one form. Of these, several grow by the mere introduc- 

 tion of one of their thick fleshy leaves into a soil of almost any kind that is 

 sufficiently dry ; they obtain an erect position, but never root, or shoot 

 forth radiclfis : and hence almost the whole of their moisture must neces- 

 sarily be derived from the surrounding atmosphere. 



Perhaps one half of the fuci have no root whatever : many of them, in- 

 deed, consist of vesicles or vesicular bulbs alone, sessile upon the matrix 

 of some stone or shell that supports them, and propagate their kinds by 

 offsets, without any other vegetable organs. The seeds of the fucus prolifer 

 sometimes evolve nothing but a leaf ; the plant being propagated also by 

 leaf upon leaf, either forked or elliptic, without root. 



The aphyteia hydnora is a curious instance in point. This plant is equally 

 destitute of leaves, stem, and root ; and consists alone of a sessile, cori- 

 aceous, and succulent flower, eaten as a luxury by the Hottentots, and para- 

 sitic to the roots of the euphorbia Mauritanica ; flower propagating flower 

 from generation to generation. 



But perhaps the plant most decisive upon this subject is the aerial epi- 

 dendrum^l first, if I mistake not, described by that excellent Portuguese 

 phytologist Loureiro, and denominated aerial from its vfery extraordinary 

 properties. This is a native of Java and the East Indies beyond the 

 Ganges ; and, in the latter region, it is no uncommon thing for the inha- 

 bitants to pluck it up, on account of the elegance of its leaves, the beauty of 

 its flower, and the exquisite odour it diflfuses, and to suspend it by a silken 

 cord from the ceilings of their rooms ; where, from year to year, it con- 

 tinues to put forth new leaves, new blossoms, and new fragrance, excited 

 alone to new life and action by the stimulus of the surrounding atmosphere. 



That stimulus is oxygene ; ammonia is a good stimulus, but oxygene 

 possesses far superior powers, and hence without some portion of oxygene 

 few plants can never be made to germinate. Hence, too, the use of cow- 

 dung and other animal recrements, which consist of muriatic acid and am= 



=^ Trapa natms. 



t Cactus ceccinell^er. 



X Epiden^rum fio9 aens'n 



