654 THE RHINOCEROS. 



one part we have breccia of altered marl or slate in quartz, and 

 various amygdaloids. It is curious to observe the different forms 

 which silica assumes. We have it in claystone porphyry here, 

 in minute round globules, no larger than turnip-seed, dotted 

 thickly over the matrix ; or crystallized round the walls of cavi- 

 ties, once filled with air or other elastic fluid ; or it may appear in 

 similar cavities as tufts of yellow asbestos, or as red, yellow, or 

 green crystals, or in laminae so arranged as to appear like fossil 

 wood. Vungue forms the watershed between those sand rivulets 

 which run to the N.E., and others which flow southward, as the 

 Kapopo, Ue, and Due, which run into the Luia. 



We found that many elephants had been feeding on the fruit 

 called Mokoronga. This is a black-colored plum, having purple 

 juice. We all ate it in large quantities, as we found it delicious. 

 The only defect it has is the great size of the seed in comparison 

 with the pulp. This is the chief fault of all uncultivated wild 

 fruits. The Mokoronga exists throughout this part of the country 

 most abundantly, and the natives eagerly devour it, as it is said 

 to be perfectly wholesome, or, as they express it, " It is pure fat," 

 and fat is by them considered the best of food. Though only a 

 little larger than a cherry, we found that the elephants had stood 

 picking them off patiently by the hour. We observed the foot- 

 prints of a black rhinoceros {Rhinoceros bicornis, Linn.) and her 

 calf. We saw other footprints among the hills of Semalembue, but 

 the black rhinoceros is remarkably scarce in all the country north 

 of the Zambesi. The white rhinoceros {Rhinoceros simus of Bur- 

 chell), or Mohohu of the Bechuanas, is quite extinct here, and 

 will soon become unknown in the country to the south. It feeds 

 almost entirely on grasses, and is of a timid, unsuspecting dispo- 

 sition : this renders it an easy prey, and they are slaughtered 

 without mercy on the introduction of fire-arms. The black pos- 

 sesses a more savage nature, and, like the ill-natured in general, is 

 never found with an ounce of fat in its body. From its greater 

 fierceness and wariness, it holds its place in a district much longer 

 than its more timid and better-conditioned neighbor. Mr. Oswell 

 was once stalking two of these beasts, and, as they came slowly to 

 him, he, knowing that there is but little chance of hitting the 

 small brain of this animal by a shot in the head, lay expecting 

 one of them to give his shoulder till he was within a few yards. 



