351 



mineral constituents of . its surface layers contribute to the 

 production of a complicated environment, whose effects upon 

 the life-functions and structure of its vegetation would 

 undoubtedly repay a close and continuous study. It would be 

 difficult to find a more favourable region for the establishment of a 

 Desert Botanical Laboratory. It may be hoped that some day the 

 example set by the Carnegie Institute in the foundation and 

 equipment of the Tucson Laboratory will be followed in the 

 establishment in the Namib of a similar centre for research 



Cultivation.— Of cultivation on the Namib plateau there is none. 

 In the river-beds several farmers have settled and have been 

 successful in the culture, under irrigation, of mealies (Zea Mays), 

 cucumbers, melons, and other cucurbitaceous fruits, as well as of 

 various vegetables. A few date palms have also been planted. 

 I was informed that both the vine and tobacco are grown in the 

 Swakop bed below Haikamchab, but saw neither. The native 

 vegetation of the river-beds affords good grazing for cattle and 

 goats. The fruits of the Ana tree, Acacia alOida, are greatly 

 relished by cattle. 



Transition from the Namib to the Acacia Park Forest. 



The transition zone from the Namib flora to that of the Acacia 

 formation is entered between Pforte and Jakalswater on the 

 Government railway, and about 10 miles north of Rossing station 

 on the Otavi line. 



Flora-While the desert flora is still represented by such 

 characteristic plants as Zygophyllum Stap/ii and the small Btephans 

 already mentioned, a change is noticeable owing to the occurrence 

 of new forms whose abundance gives a different character to the 

 flora. There is also a marked increase in the number of species 

 of grasses. Of the new forms the most conspicuous are a dwari, 

 spreading Acacia ( ? A. heteracantha, Burch.),and a bushy, tere te- 

 stemmed, leafless Euphorbia forming large clumps 5-8 teet nign , 



this is evidently the same species as that P hoto ^ ra P^^ by S c f,!^„ 

 at Guos, 200 miles to the south (Schimper, Fig. 3b0). Between 

 30 and 40 km. north of Rossing (on the Otavi rai way) this p > ant 

 becomes so abundant as to constitute a wel "^™ fXj 

 formation. The station Sphinx is situated on a plain ^rrounde 

 by hills whose slopes are studded with low bush f ~ n ° ^I 

 mostly Acacias. This is the most marked change yet noticed, tor 

 the Namib hills as seen from a distance appear to be qn it > tu le or 

 vegetation. Beyond Sphinx a pnrple- flowered Sf™™™ « 

 met with, a herb 2-3 feet high, ^hich rapidl increases in 



importance, and remains a common plant for ^^JmeTl^ 

 Commiphora saxicola, already seen at Haikamchab becomes very 

 abundant a few miles further on where mdeed it is toe 

 predominant plant in a scrub which » ls ?™^*J2i 

 dwarf AcaciasT About the same V^.^ h ^ e ^ B Z^ 

 Don., is met with for the first time ; it is a fj^^f ™* 

 with large, white flowers and is a prominent plant all the way 

 to the high plateau east of Windhuk. Near the ^ nex staUon 

 after Sphinx-situated at the head of a small channel tributary 



