NA TURE 



49 



THURSDAY, MAY 17, il 



FLORA OF THE HAWAIIAN ISLANDS. 



Flora of the Hawaiian Islands j a Description of their 

 Phanerogams and Vascular Cryptogams. By William 

 Hillebrand, M.D. Annotated and Published after the 

 Author's death by W. F. Hillebrand. 8vo, pp. 673, 

 with Frontispiece and Four Maps. (London : Williams 

 and Norgate, 1888.) 



THE Sandwich Islands, from a botanical point of 

 view, are a group of peculiar interest. There are 

 about a dozen of them, and they form an area of which 

 the northern end falls just within the tropical zone, at a 

 distance of 2000 miles from America, and separated from 

 it by a deep gulf. From the nearest points of Polynesia 

 proper, the Marquesas Islands and Tahiti, they are 

 distant i860 and 2190 miles. The largest island, Hawaii, 

 is the most southern of the group. It has an area of 

 about 5000 square miles, and its mountains, one of which 

 is an active volcano, rise to a height of nearly 15,000 

 feet. The other islands, all taken together, are not equal 

 to more than half the area of Hawaii. The capital of 

 the group, Honolulu, is situated on the south side of the 

 small island of Oahu. The average annual temperature 

 of Honolulu is 75 F., the general range of the thermo- 

 meter being from 70 to 83 , so that within an area about 

 equal to that of Yorkshire we have every variation of 

 temperature from equatorial heat to perpetual snow. 

 Dr. Hillebrand estimates the total flora of the islands 

 (Phanerogamia and Vascular Cryptogamia) at 999 species, 

 representing 365 genera, and 99 orders. Of these 999 

 species, 653 are absolutely restricted to the Sandwich 

 Islands, 207 native species are known elsewhere, 24 

 species were introduced by the natives in remote times, 

 and 115 species are weeds of recent introduction. 

 Leaving the introductions out of account, we have 

 therefore a native flora of 860 species, of which three out 

 of four are endemic. A vegetation thus individualized 

 makes the group one of the most interesting fields of study 

 in the world. 



Dr. Hillebrand may be said to have devoted his life 

 to the study of this question. He was born in West- 

 phalia in 1 82 1, and studied medicine at Gottingen, 

 Heidelberg, and Berlin. After taking his degree, he 

 settled down for a short time in practice in Germany, but 

 his health soon broke down, and he sailed for Australia. 

 After visiting the Philippine Islands and California, he 

 made the Sandwich Islands his home, and his health 

 became quite restored. He lived at Honolulu, mastered 

 the language, and practised his profession with great 

 success. He became private physician to the king, a 

 member of the Privy Council, an active member of the 

 Board of Health, and physician to the Queen's Hospital 

 and the principal lunatic asylum. During'twenty years he 

 devoted his leisure to working out the botany of the 

 group, and sent large collections to Kew and other 

 European herbaria. He left the islands in 1871, but 

 kept up a regular correspondence with various residents 

 who were interested in botany, and who sent him further 

 collections. He died in July 1886, just after completing 

 the descriptive portion of this present work, which has 

 Vox,, xxxviii. — No. q68. 



been edited by his son, who lives in America, and who 

 has prefixed to it the introduction which was drawn up 

 by Mr. Bentham for our British colonial floras. His 

 name is commemorated by the genus Hillebrandia, 

 which is the only representative of the Begoniacece in 

 Polynesia, and which was named after him by Prof. 

 Oliver. The type specimens of the present work have 

 been presented to the Berlin Herbarium, and the Prus- 

 sian Government has made a grant towards the expense 

 of its publication. 



The book, which is dedicated to the Hawaiian people, 

 consists almost entirely of careful descriptions, in English, 

 of the orders, genera, species, and varieties, that form 

 the flora, accompanied by full details of their distribution 

 through the different islands, and the sort of places in 

 which they grow. Nearly all the native plants are trees, 

 shrubs, or perennial herbs. Comparing the islands with 

 one another, Dr. Hillebrand's general view is that the 

 flora of Kaui, the comparatively small north-eastern 

 island of the group, is the richest and most individualized, 

 and that of the large southern island of Hawaii, where 

 the mountains rise the highest, is the most monotonous 

 and least attractive. The total number of species here 

 described as new is 180, but in some cases, as, for 

 instance, by Mr. C. B. Clarke, in his " Monograph of the 

 Cyrtandraceas," issued in 1883, the publication of these 

 has been anticipated, and the earlier names will have to 

 be adopted. It is much to be regretted that the author 

 did not live to work out fully his generalizations. A great 

 deal has been written during the last few years on the 

 general subject of plant-distribution, and in particular 

 Wawra and Engler in Germany, and in England 

 Wallace in " Island Life," and Hemsley in the u Botany 

 of the Challenger," have discussed the various points of 

 interest connected with the flora of these islands. What 

 is wanted now is that Dr. Hillebrand's added facts 

 should be compared together and summarized, and that 

 the general conclusions which they establish should be 

 carefully traced out. 



The following is his outline of the zones of vegetation 

 and their characteristics : — 



" (1) The Lowland Zone. — Open country, grass-covered 

 after the rains, with isolated clump's of trees, represented 

 by Paritium tiliaceum, Erythrina, Reynoldsia, Pan- 

 danus, Capparis, Gossypium, Abutilon incanum. This 

 includes also the littoral zone. 



" (2) The Lower Forest Zone. — Tropical in character, its 

 upper limit between 1000 and 2000 feet above the sea. 

 Its physiognomy is marked distinctly by Aleurites moluc- 

 cana, the pale foliage of which, in contrast with the green 

 colour around, attracts at once the eye of the beholder. 

 The woods are rather open ; Zinziber Zernmbet covers 

 the ground. Cordyline, Eugenia domestica, Zinziber 

 Zerumbet, and other species, are strictly confined to it. 

 Pandanus odoratissimus and Paritium tiliaceum do not 

 pass beyond it, but Freycinetia does. To its upper por- 

 tion, but extending also into the lower part of the next 

 zone, belong also most Sapotacecc, Apocynacece, Gardenia, 

 Psychotria, Maba, most Urticacew, Pisinia, Ela^ocarpus, 

 Aurantiacece, and others. 



" (3) The Middle ForestZone. — Thislieswithinthe region 

 of clouds, and develops the greatest luxuriance in trees 

 and jungle. Pelea and Cheirodendron are representative 

 genera. The prevailing trees are indeed Metrosideros 

 polymorpha and Acacia Koa; but, although they reach 

 here their greatest development in size and number, they 



