ILLUSTRATIONS (13). PHANEROGAMIC PLANTS. 293 



the equator, in the New Continent, with the floras of Oaxaca, 

 Yucatan, Guatemala, Nicaragua, the Isthmus of Panama, the 

 Choco, Antioquia, and the Province de los Pastes; while 

 south of the equator, we are equally ignorant of the floras 

 of the boundless forest-region between the Ucayale, the 

 Rio de la Madura, and the Toncantin (three mighty tribu- 

 taries of the Amazon), as well as of those of Paraguay and 

 the Province de las Missiones. In Africa, we know nothing 

 of the vegetation of the whole of the interior, between 

 15 north and 20 south lat. ; and in Asia we are unac- 

 quainted with the floras of the south and south-east of 

 Arabia, where the highlands rise to an elevation of 6400 

 feet; as also with the floras between the Thian-schan, the 

 Kuen-Liin, and the Himalaya; those of Western China; 

 and those of the great portion of the countries beyond the 

 Ganges. Still more unknown to botanists are the interior 

 portions of Borneo and New Guinea, and of some districts 

 of Australia. Further to the south the number of the 

 species decreases in a most remarkable manner, as Joseph 

 Hooker has ably shown, from his own observation, in his 

 Antarctic Flora. The three islands which constitute New 

 Zealand extend from 34^ to 47 of latitude, and as they have 

 besides snow-crowned mountains more than 8850 feet in height, 

 they must exhibit considerable differences of climate. The most 

 northern island has been explored with tolerable accuracy 

 from the time of Banks and Solander's voyage (with Capt, 

 Cook), to the visits of Lesson, the brothers Cunningham, and 

 Colenso ; and yet in more than seventy years, the number of 

 Phanerogamia with which we have become acquainted is 

 below 700. * This paucity of vegetable species corresponds 

 with the paucity of animal forms. Dr. Joseph Hooker has 

 observed that "Iceland, proverbially barren as it is, and upon 

 which no tree, save a few stunted birches, is to be found, pos- 

 sesses five times as many flowering plants as Lord Auckland's 

 group and Campbell's Islands together, although these are 

 situated at from 8 to 10 nearer the equator in the southern 

 hemisphere. The antarctic flora is at once characterised by 

 uniformity and great luxuriance of vegetation, which is attri- 

 butable to the influence exerted by an uninterruptedly cool and 

 humid climate. In Southern Chili, Patagonia, and Tierra del 

 * Ernest Dieffenbach, Travels in New Zealand, 1843, vol. i. p, 419. 



