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. _To Australasia_--Goodeniaceæ, Epacridaceæ, Stackhousiaceæ, Brunoniaceæ, Tremandraceæ. [A group of plants occurring only in one of the six great divisions of the world is called _monomic_, (from μονος _one_, and νομὸς, a _region_).