254 A NATURALIST IN THE PACIFIC chap. 



district, associated with Cyrtandrse, Marattias, and true Tree-Ferns, 

 the ground being covered with Lycopods, the " Tree-Lobelias " 

 abound. I noted four kinds within two hundred yards. Of the 

 humidity of the upper slopes of Mount Eeka I have a very vivid 

 recollection, and my experience of passing a night on that mountain 

 is described in Chapter XIX. 



The Lobeliacese, as Hillebrand remarks, occur invariably as 

 isolated individuals. I was often struck, however, with the prefer- 

 ence the genera showed for particular localities. Thus, Clermontia 

 is well represented on the western slopes of Mount Eeka, Delissea 

 on the northern slopes of Hualalai (3,800 to 4,500 feet), Cyanea on 

 the Hamakua slopes of Mauna Kea (2,300 to 4,100), and Lobelia 

 on the southern slopes of Mauna Loa behind Punaluu (2,000 to 

 3,500 feet). 



To the student of geographical distribution the Hawaiian 

 Lobeliacese are of especial interest. Mr. Hemsley observes that 

 they have their greatest affinities in America {Intr. Bot. Chall. 

 Exped., p. 68). M. Drake del Castillo, in his " Memoire couronne 

 par l'Academie des Sciences" (Paris, 1890), remarks that these 

 plants connect Hawaii with America just as the Goodeniacese link 

 the same group with Australia. This is what we might have 

 expected since the centre of the order is in America, principally in 

 the Mexican and Andine regions (Drake del Castillo, Flore Polyn. 

 Franc, xi.). 



Though five out of the six genera are endemic, the sixth, that 

 of Lobelia, has a world-wide distribution. Here then, we have 

 a genus that belongs strictly to the next or second stage of the 

 plant-stocking of the Hawaiian Group, namely, when the non- 

 endemic genera now containing endemic species were introduced. 

 As with the Composite genera, Campylotheca and Lipochaeta, 

 Lobelia marks the beginning of the new or the close of the old era. 

 It is, however, necessary to point out that many of the conditions 

 favouring luxuriant and rank vegetable growth are pre-eminently 

 represented in the zone of the Lobeliacese. In these soft-stemmed 

 plants with their copious milky sap and large fleshy flowers, some- 

 times two or three inches long, the very redundancy of growth 

 would tend both to exaggerate and to disguise the generic distinc- 

 tions. To the ordinary observer these " Tree-Lobelias " call up 

 vague notions of a flora of a bygone age, and by their bizarre 

 appearance he might with some excuse be led to give play to his 

 imagination when describing them ; but the systematic botanist, 

 seeing through their disguise, frames rather more prosaic notions of 



