270 MR. D’URBAN ON THE NATURALIZED WEEDS 
Zinnia elegans, Mirabilis Jalapa, Ipomea purpurea, and Canna In- 
dica (which spread themselves rapidly over gardens and become 
weeds where they have once been sown), because they are not ge- 
nerally diffused. Of the Morning Glory or Jpomea at least four 
crops come up in the season; and its voluble habit renders it a 
most unwelcome plant in a flower-garden, in spite of its exquisitely 
beautiful flowers of every hue. It speedily smothers everything 
else, and from its rapid growth is most exhaustive to the soil. 
You will see that, with the exception of five species, namely 
Malva parviflora, Tribulus terrestris, Emex spinosus, Ricinus com- 
munis, and Hordeum murinum, and two species whose original 
habitats are unknown to me, the whole of the thirty-two plants in 
my list are found in North America either native or naturalized, 
and many of them may therefore have been introduced from thence 
with the American garden seeds which are so largely imported 
into South Africa, Indeed this is the popular view of their 
origin in the colony itself. Tribulus terrestris and Emex spinosus 
are perhaps native weeds. 
The Fumaria is that form of officinalis, Linn., called var. Ca- 
pensis, and supposed by Dr. Sonder to be identical with F. muralis 
of the ‘ Flora Germanica.’ 
The Medicago has two to three coils in the pod, and is probably 
denticulata, Wild. 
The Common Purslane (Portulaca oleracea) spreads itself in 
dense mats over the gardens in an astonishing manner. It is 
not, I think, generally known in England that the South African 
antelopes do not eat grass, but live entirely on suceulent shrubs 
and bulbs. A tame Duiker Bok (Cephalophus Grimmia) confined 
in our garden at King William's Town previously to my arrival 
there had been fed principally upon “Spell-boom’” or Tree- 
Purslane (Portulacaria Afra), a dwarf state of which is used as an 
edging to the flower-beds, but knowing its affinity with the 
Garden Purslane, I was induced to offer the latter to the Duiker, 
which ate it with great avidity. Might not this hint be useful to 
the authorities of the Zoological Gardens, who do not seem to have 
hitherto been particularly successful in the management of their 
South African antelopes, judging from the numerous deaths which 
have occurred amongst Sir George Grey's magnificent donations ? 
The Thorny Clotbur (Xanthium spinosum) has spread with such 
rapidity along the roadsides, around the military posts, and in all 
waste places, as to occasion great alarm amongst the sheep-farmers 
and others interested in the wool trade, the prickly involucre 
