12 Dansk Botanisk Arkiv, Bd. 2. Nr. 8. 



individuals, nor on all branches of one and the same individual. 

 This Adansonia is the characterising tree of the savannah forest 

 of the north-western Australia and gives it a resemblance to the 

 African savannah forest, in which Adansonia digitata is the pro- 

 minent feature. 



Also from a plant-geographical point of view its existence is 

 interesting, as the genus Adansonia, with this single exception, is 

 confined to tropical Africa including Madagascar. On the African 

 continent only A. digitata occurs, and it is an open question 

 whether it owes its ocurrence there to the inhabitants (the negros 

 etc.) or is really spontaneous; bat in Madagascar the genus has 

 several species besides A. digitata. This distribution suggests that 

 the genus has had its real home in Madagascar or, better, on 

 the sunken continent of which Madagascar is a remainder, and 

 that it has from there outposts both towards east, where A. Gregor ii 

 arose in tropical North-Australia, and towards west, where A. 

 digitata invaded tropical Africa. 



Next to Adansonia the white-barked "Gums" {Eucalyptus cla- 

 vigera var. Dallachyana and E. pyrophora) were common. E. cla- 

 vigera var. Dallachyana, which was the commoner, had long pen- 

 dulous outer branches which were moved by the wind. Gyrocar- 

 pus americanus (var. acuminatus) and Bauhinia Cunninghamii were 

 also common. Gyrocarpus is a low tree with a soft wood and thick, 

 light bark; its leaves are much like those of poplar, and it its 

 a deciduous tree which had just got new leaves at the time of my 

 visit. Its peculiar fruits, with the two long wings (see Fig. 5), resemble 

 very much the fruits of the Dipterocarpaceæ. Bauhinia is a low 

 tree with densely branching, dense dark-green foliage and large 

 red-brown pods. Other trees were: Ficus indecora, S ant alum lan- 

 ceolatum, Phyllanthus reticulatus (var. glober), Atalaya hemiglauca, 

 Carey a australis, Hakea sp., Acacia sp. The vine-like Tinospora 

 smilacina was often seen climbing in the trees, and several Loran- 

 JAws-species (see p. 14) infested the trees (noted on Adansonia, 

 Eucalyptus, Ficus and Hakea). 



The trees stand with open spaces between them, like the trees 

 o£ a park (see Plate III, Fig. 1), and leave no shade. They do 

 not reach to any considerable height. Some of them are ever- 

 green (Eucalyptus, Atalaya, Hakea, Bauhinia etc.), others are 

 deciduous (Adansonia, Gyrocarpus) and are leafless during the dry 

 winter-time. The evergreen species have, of course, xerophytic 

 leaves, but the xeromorphy consists mainly in leathery consistence, 

 not in coverings of hairs nor in succulence. 





