CHAP. XIII.] 
THE GALAPAGOS ISLANDS. 
277 
1851, founded on Mr. Darwin’s collections, and a later paper by 
N. J. Andersson in the Linncea of 1861, embodying more recent 
discoveries. 
The total number of flowering plants known at the latter 
date was 332, of which 174 were peculiar to the islands, while 
158 were common to other countries. Of these latter about 
twenty have been introduced by man, while the remainder are 
all natives of some part of America, though about a third part 
are species of wide range extending into both hemispheres. Of 
those confined to America, forty-two are found in both the 
northern and southern continents, twenty-one are confined to 
South America, while twenty are found only in North America, 
the West Indies, or Mexico. This equality of North American 
and South American species in the Galapagos is a fact of great 
significance in connection with the observation of Sir Joseph 
Hooker, that the peculiar species are allied to the plants of 
temperate America or to those of the high Andes, while the 
non-peculiar species are mostly such as inhabit the hotter 
regions of the tropics near the level of the sea. He also 
observes that the seeds of this latter class of Galapagos plants 
often have special means of transport, or belong to groups whose 
seeds are known to stand long voyages and to possess great 
vitality. Mr. Bentham also, in his elaborate account of the 
Compositae, 1 remarks on the decided Central American or 
Mexican affinities of the Galapagos species, so that we may 
consider this to be a thoroughly well-established fact. 
The most prevalent families of plants in the Galapagos are 
the Compositae (40 sp.), Graminese (32 sp.), Leguminosae (30 
sp.), and Euphorbiaceae (29 sp.). Of the Compositae most of 
the species, except such as are common weeds or shore plants, 
are peculiar, but there are only two peculiar genera allied to 
Mexican forms and not very distinct ; while the genus Lipochaeta, 
represented here by a single species, is only found elsewhere in 
the Sandwich Islands, though it has American affinities. 
Origin of the Galapagos Flora , — These facts are explained 
by the past history of the American continent, its separation at 
1 Journal of the Linnean Society , Vol. XIII., “Botany,'’ p. 556. 
