BEEADTH OF OUTLOOK 413 



examined samples of Diatomaceous Ooze from the ocean-floor 

 of the Antarctic, and so initiated the systematic treatment 

 of the organic deposits of the deep sea. These, together 

 with his observations on glaciers and on sub-aerial denudation, 

 were all carried out in his earlier years of travel. The quality 

 and the rapidity of the work showed his mastery in a science 

 not specially his own ; while the problems which he handled 

 were all nascent at the time when he worked upon them. 



But though such excursions into the sphere of the kindred 

 sciences illustrate Hooker's natural power and the breadth 

 of the basis of observation upon which he worked, his fame 

 rests upon his purely botanical writings. The most important 

 of them fall into three groups, though these naturally over- 

 lap : viz. the works of Systematic, of Morphological, and of 

 Philosophical character. His greatest Systematic Works were 

 the ' Antarctic Flora,' the ' Flora of British India,' the ' Genera 

 Plantarum,' and the ' Kew Index.' As all of these four differ 

 in scope and character, each demands separate notice and 

 analysis. 



On the Antarctic Voyage Hooker had the opportunity 

 of collecting on all the great circum-polar areas of the Southern 

 Hemisphere. His 'Antarctic Flora ' was based on the collections 

 and observations then made, supplemented by those of other 

 travellers. It was published in six large quarto volumes. 

 They describe about three thousand species, of which over 

 one thousand are depicted, usually with detailed analytical 

 drawings. But there is more in them than reports of ex- 

 plorations or descriptions of new species. All the known 

 facts that could be gathered were incorporated, so that they 

 became systematically elaborated and complete Floras of 

 the several countries. Moreover, in the last of them, the 

 ' Flora Tasmaniae,' there is an Introductory Essay, which in 

 itself would have made Hooker famous, for it contains a dis- 

 cussion of the permanence of species, to which we shall return 

 later. It contained also his first enunciation of broad theory 

 of Geographical Distribution of Plants. While it was still 

 in preparation Darwin wrote to him in terms of prophetic 

 enthusiasm : ' I know I shall live to see you the first authority 



