The wind next day was not propitious, and the boats were obliged to stay beside a grass tangle by the bank. I made use of the detention to enjoy a little fishing for water-plants. The water-lilies surpassed all description, and would adorn any Victoria-house. Unfortunately I could not succeed in transferring to this region the queen of the waters. The _Victoria regia_ seed, which I had brought for the purpose in pots, would never germinate; perhaps, although it was preserved in water, the heat of my cabin during my voyage was too great and destroyed its vitality. I can only boast of having naturalised in this district of Central Africa two plants as representatives of culture in Europe—the sun-flower and the tomato. The river, which is ordinarily about 300 feet wide, abounds in thick masses of potamogeton, trapa, and yellow ottelia. The seeds of this last plant much resemble the sesamum, growing like the seeds of the Nymphæa in a slimy gelatinous mass; they are collected by the natives, and, after being dried, are pounded down into a sort of meal, which the sailors of Khartoom assured me was a wholesome and excellent remedy for indigestion. It surprised me very much to learn that the eatableness of the water-nut (_Trapa_) was unknown to the Dinka, although it grew in such abundance on the river. We landed, towards evening, close below the mouth of the Bahr-el-Arab in a forest of lofty trees, where the West African _Stephegyne_ appears to find its extreme eastern limit. The wood of this species of Rubiaceæ is somewhat soft and light, but its branches make masts for the boats of a strength and straightness unequalled by any other growth in these countries, where wood adapted for erections of any sort is so notably scarce. The Gazelle, at the place where the Bahr-el-Arab empties itself, has a width of about 1000 feet. This mouth is itself not much less, but just above the mouth the condition of the Gazelle is so different that it must be evident to every sailor that the Bahr-el-Arab plays a very important part in contributing to the entire system.