3 66 THE POPULAR SCIENCE MONTHLY. 



Australia.* Several species of the mosses (Funaria, Dicranum, and 

 Bryum) are common to the Blue Mountains of Jamaica, the Peak of 

 Teneriffe, and Lapland. f Among 133 plants from one of the Pyrenees, 

 Raymond found thirty-five identical with those of Melville Island in 

 the Arctic Ocean. J Potent ilia anserina grows in North America 

 from Pennsylvania to California and northward, in the northern part 

 of the Old World, in Chili, and in New Zealand ; Monotropa uniflora 

 from Canada to Louisiana, in Oregon, in New Granada (South Amer- 

 ica), and Himalaya Mountains in India ; Bichondora repens from Vir- 

 ginia to Chili, in New Zealand, in Tasmania, to eastern Africa, and at 

 the Cape of Good Hope ; Adiantum pedatum is found in the eastern 

 United States and Canada, to Oregon, in Kamtchatka, Japan, and 

 Nepaul in India ; Crantzia lineata in the United States from Massa- 

 chusetts to Texas, in South America from Buenos Ayres to Falkland 

 Islands, and in New Zealand ; Phleum alpinum inhabits the United 

 States, Switzerland, and the Straits of Magellan. || 



These few cases will suffice to show the strange and apparently 

 capricious distribution of plants. All these are, of course, supposed 

 to be indigenous to the various countries given as their habitats. 

 Now, according to the theory of natural selection and of descent with 

 modification, we must suppose that all plants have descended from 

 parents like themselves, and have not been specially created where 

 they are now found. When we find, therefore, two plants of the same 

 species, or of the same genus closely allied to each other, inhabiting 

 the United States and Europe, or Europe and New Zealand, we must 

 naturally suppose that at some time or other they had descended from 

 the same kind of an ancestor, but that owing to circumstances they 

 have become widely separated. Plants are not like animals, endowed 

 with locomotive organs, and they must therefore have depended on 

 the elements to transport them. To try and discover these modes of 

 transport, then, we shall now proceed. 



The winds undoubtedly exercise an immense influence on the distri- 

 bution of plants. Many seeds are furnished with a pappus or feathery 

 appendage, by means of which they are easily carried along by the 

 wind. Many of these belong to the Composite, such as the dandelion, 

 the thistles, hieraciums, etc. Others are provided with wings, as in 

 the ash and the maple ; still others with cottony or feathery tails, as 

 in the anemones and clematis. Again, many are so minute as to be 

 visible to the eye only in the form of smoke, and are so numerous as to 

 be almost uncountable. This is especially the case with fungi, mosses, 



* Gray's " Manual of Botany," p. 55. 

 f Humboldt's " Travels," i., p. 115. 

 \ Jussieu, he. cit., p. 712. 



These five and many others are noticed in an article by Professor Asa Gray, in 

 "Silliman's Journal," second series, vol. xxiii., p. 381, el seq. 

 || Humboldt, he. cit., i., p. 423. 



