When the chimpanzee goes on all fours, he generally supports himself on the backs of his closed fingers rather than on the palm of the hand, and he goes sometimes on the soles of his feet, sometimes on the closed toes. His gait also is weak and vacillating, and he can stand upright on his feet for a still shorter time than the gorilla. At the same time he seeks support for his hands, or clasps them above his head, which is a little thrown back, in order to maintain his balance. These animals send forth loud cries, which echo plaintively through the great tropical forests. Pechuël-Lösche says that the horrible wails, the furious shrieks and howls, which may be heard morning and evening, and often in the night, make these creatures truly hateful to travellers. “Since they are really accomplished in the art of bringing forth these unpleasant sounds, which may be heard at a great distance, and are reproduced by the echoes, it is impossible to estimate the number of those who take part in the dreary noise, but often we seemed to hear more than a hundred. They generally remain upon the ground among the dense underwood and thickets of scitamine, and only climb trees for the sake of obtaining fruit. Their track may be plainly discerned on soft ground: they stop short wherever the _amomum_ grows, of which they are very fond, and the red husks of its fruit may be seen scattered all around.” The same narrator observes that the mischievous and active sea-cat monkeys, which abound on the Loango, frequently provoke the defenceless chimpanzees by their malicious tricks until the tormented creatures cause the forest to echo with their discordant cries. These animals wander about, always in search of fresh feeding-grounds. They also construct nests and, as Koppenfels states, the male passes the night below the nest of his family, which is placed on a forked branch. Du Chaillu asserts that the Nschiego-Mbouvé also builds a pent-house. An illustration of this structure, which is only moderately successful, and has undoubtedly been embellished in London, is given by him. Koppenfels believes that the so-called pent-house is only the family nest, under which the male places himself; while Reichenfels thinks it possible that some parasitic growth, perhaps a _Loranthus_, gave rise to the belief that such a pent-house is erected.