32 THE VOYAGE OF H.M.S. CHALLENGER. 



Pharnaceum acidum (Ficoidese), St Helena, is less woody than several of the South 

 African species of the genus. 



Bwpleurum (Uinbelliferse), Juan Fernandez, has an analogue in the South European 

 Bupleurumfruticosum; and the tropical African genera Steganotcenia and Hcteromorpha 

 include truly arboreous species, which the Juan Fernandez Buplcura are not. 



Lobdiacece, Sandwich and Society Islands : the endemic genera of this order are repre- 

 sented by equally tall and woody members, belonging to the genera Centropogon and 

 Syphocampylus, &c, in America. 



Echium in the Canaries, Hdiotropium in St Helena, and Sdkirkia in Juan Fernandez, 

 belonging to the B-oragineae, are represented in South Africa by many truly shrubby 

 species of Lobostemon. 



Cmninia (Labiatse), Juan Fernandez : the species of this genus are surpassed in size 

 by the South American Tlyptis membranacea, which grows thirty to forty feet high, and 

 equalled by Hyptis arborea from the same country ; and there are many large shrubby 

 and subarboreous Labiatse in Australia and India. 



Plantago : the St Helena, Juan Fernandez, and Sandwich Islands species of this genus 

 are unapproached in their character of miniature trees, with an unbranched stem, by any 

 continental species that we have seen ; yet some of the South American species are 

 woody. Wawra (Flora, 1874, p. 563) states that the stem of the Sandwich Island Plan- 

 tago princeps is sometimes as much as six feet high. 



So far, then, as these insular woody plants are concerned, and the same holds good for 

 the arboreous Compositas, which constitute so prominent a feature in the vegetation of 

 several oceanic islands, they cannot be regarded as peculiarly insular, though they largely 

 characterise insular floras. Instances of shrubby and arboreous species of orders, or of large 

 genera otherwise herbaceous or shrubby, are not wanting in larger islands and continents. 

 The shrubby Veronicas of New Zealand culminate in Veronica elliptica, Forst, which is 

 arboreous in favourable situations, attaining a height of twenty feet ; and, what is more 

 remarkable, this species inhabits New Zealand, the Chatham, Auckland, and Campbell 

 Islands, and South Chili, Fuegia, and the Falkland Islands. This, however, is not adduced 

 as a special instance. In Chili there is the shrubby Oxalis gigantea, which grows three to 

 six feet high, and there are several shrubby species of Viola; but the localities where 

 they grow are probably as insular in their physical conditions, except isolation, as the 

 islands themselves. 



INDIGENOUS AND ENDEMIC GENERA AND SPECIES OF FLOWERING 

 PLANTS IN VARIOUS ISLANDS AND CONTINENTAL AREAS. 



The vegetation of some of the remote oceanic islands is remarkable for the large 

 number of endemic genera and species it contains, but not more so than that of some 



