Such, in our opinion, is the number which approximatively represents the lower limit of the aggregate of vegetable species (phanerogamous and cryptogamous) inhabiting our planet. The innumerable individuals of this half-million of species are born, and live, and reproduce their kind, and die, like the twelve hundred millions of individuals of our solitary human species. The former, it is true, remain fixed to the soil which has witnessed their birth, while the latter wander, more or less freely over the terrestrial surface. Do not animals enjoy the same privilege of locomotion? Undoubtedly. But men boast of the reason and the conscience with which they are endowed. Agreed. But with the exception of a small number—the infinite minority of progress—to what advantage have men employed the reason and the conscience of which they boast?
But this is a digression. We proceed to place before the reader a few final data in illustration of the subject we have been considering—the number of existing vegetable species.
The following is an estimate of the known species of plants on the globe at different dates:—
| Phanerogams. | Cryptogams. | Total. | |||
|---|---|---|---|---|---|
| According to | Linnæus, | 1753, | 5,323 | 615 | 5,938 |
| Pusoon, | 1807, | 19,949 | 6,000 | 25,949 | |
| Stendel, | 1824, | 39,684 | 10,765 | 50,649 | |
| Stendel, | 1841, | 78,000 | 13,000 | 91,000 | |
| Stendel, | 1844, | 80,000 | 15,000 | 95,000 |
The advance made of late years in the knowledge of existing species will be apparent from a consideration of Lindley's estimate in 1846:—
| Genera. | Species. | |
|---|---|---|
| Thallogens, | 939 | 8,394 |
| Acrogens, | 310 | 4,086 |
| Rhizogens, | 21 | 53 |
| Endogens, | 1,420 | 13,684 |
| Dictyogens, | 17 | 268 |
| Gymnogens, | 37 | 210 |
| Exogens, | 6,191 | 16,225 |
| ——— | ——— | |
| Total, | 8,935 | 92,920 |
According to Hinds, the following families are almost entirely restricted to particular divisions of the globe:—
To Europe—Globulariaceæ, Ceratophyllaceæ.
To Asia—Dipterocarpaceæ, Aquilariaceæ, Camelliaceæ, Moringaceæ, Stilaginaceæ.
To Africa—Bruniaceæ, Brexiaceæ, Belvisiaceæ, Penæaceæ.
To North America—Sarraceniaceæ.
To South America—Rhizobolaceæ, Gillesiaceæ, Calyceraceæ, Vochysiaceæ, Simarubaceæ, Monimiaceæ, Humiriaceæ, Papayaceæ, Gesneraceæ, Lacistemaceæ.