Part 46

J. Thomson. Through Masai Land.

Emin Pasha in Central Africa. Edited by Schweinfurth, Ratzel, Felkin, and Hartlaub. London, 1885.

Also well-known works by Livingstone, Stanley, &c.

Note 38: p. 170.--Heat in the Desert.

50° Celsius, or Centigrade = 122° Fahrenheit. Temperatures of 121°, 122°, 133° Fahr., and so on, have been repeatedly recorded in the desert. Solymos, in his Desert Life, notes 115° Fahr. in the shade as the maximum for his year. He also calls attention to the frost and ice! “Duveyrier registered frost twenty-six times between December and March in the plains of the Central Sahara.” His picture of the desert-well is much less optimistic than Brehm’s.

Note 39: p. 173.--The Termites.

Termites or “white ants” are very characteristic, wood-eating insects of tropical Africa and other warm countries. Though not related to the true ants, they have somewhat similar social organizations.

The reader will be rewarded who turns to Prof. Henry Drummond’s Tropical Africa, where there is not only a graphic description of the ways of the termites, but an interesting theory of their possible agricultural importance. As they avoid the light, and travel on the trees only under cover of their tunnels of finely-comminuted and cemented earth, they must be continually pulverizing the soil. When rain-storms come this fine dust is washed from the trees, and some of it may go to swell the alluvium of distant valleys. Hence the termite may be, like the earthworm, a soil-maker of considerable importance. Mr. H. A. Bryden, in his Gun and Camera in Southern Africa (London, 1893), writes as follows of the termites: “Our cases, portmanteaus, &c., were arranged round, but not touching the walls. Every article reposed on glass bottles, as the only known protection against the depredations of white ants.... They will eat large holes in a thick tweed coat in one night, and anything softer than metal left to their tender mercies for a night or two is irretrievably ruined.... If the huts are inspected every few days, the tunnels of self-made mortar can be swept away, and the depredator kept at all events to the flooring.... Most housewives have, at least once a year, to institute a crusade against the marauders, dig up the flooring, and attempt to find the queen. If the queen-ant can be successfully located and dug up, the nuisance is ended; the rest of the ants, bereft of their sovereign, at once quit the building, and for a season trouble no more.... In the forests to the north and west the mischief done by these insects is enormous. The tree is attacked, the tunnels are run up along the bole, the wood is pierced and riddled, and the work of destruction is soon completed.”

There is, however, a lack of precise observation as to the extent to which termites attack trees which are altogether sound and living. In great measure they merely hasten and complete a destruction for whose initiation they are not responsible.

Note 40: p. 173.--Summer Sleep.

Summer-sleep in torrid regions, affecting a few fishes, amphibians, and reptiles, is a phenomenon analogous to hibernation elsewhere, but its physiological explanation is even more obscure.

Note 41: p. 174.--The Karroo.

Karroo, a general name for the highland steppes of South Africa. See H. A. Bryden’s Kloof and Karroo (1889).

Note 42: p. 178.--Cerastes (Vipera hasselquistii).

The horned viper is the most common viper of Northern Africa. It is extremely poisonous. It is of a brownish-white colour with darker markings, and has a scaly spine or horn over each eye. This species is usually supposed to have been Cleopatra’s asp.

Note 43: p. 182. See Note 39.

Note 44: p. 183.--The mud-fish.

This remarkable animal (Protopterus) is one of the Double-breathers or Dipnoi, a member of a small class between Fishes and Amphibians, represented by three genera--Ceratodus in Queensland, Lepidosiren in Brazil, and this Protopterus in Africa. They differ in many ways from other fishes, being physiologically intermediate between Fishes and Amphibians. Hundreds of specimens have been brought within their ‘nests’ from Africa to Europe. Brehm speaks of the complete enclosure of the capsule, but this is now known to communicate with the outer world by a tubular passage through the mud. At the foot of this tube the mud-fish keeps his nostrils. The lung is a specialization of the swim-bladder which is present in most fishes.

Note 45: p. 184.--The Royal Aspis or Uräus.

The Uräus snake or Aspis is the well-known Egyptian jugglers’ snake (Naja haje). It may be over six feet in length, and is very deadly.

Note 46: p. 185.--Spitting poison.

The poison of a snake is contained in the secretion of a specialized salivary gland. The compression of this venom gland propels the fluid along a duct which leads to the groove or canal of the fang. Infection with the venom only occurs when, by more or less of a bite, the poison is injected into the victim. No spitting of poison is known, nor would it have effect without a wound.

Note 47: p. 186.--The Gecko.

Figures and a brief description of the gecko’s clinging foot will be found in Semper’s well-known Animal Life (International Science Series, 1881). The clinging power is due to numerous long bristle-like hairs on the sole of the foot. These appear to be modifications of the “casting-hairs” which are used in “skin-casting”.

Note 48: p. 191.--Dance of Ostrich.

A vivid picture of the Ostrich dance will be found in Prof. Lloyd Morgan’s Animal Sketches (1892).

Note 49: p. 192.--Ostrich.

Prof. Newton, in his Dictionary of Birds, notes that Ostriches, though sometimes assembling in troops of 30-50, commonly live in companies of four or five--one cock and the rest hens. This is especially true at the breeding season. All the hens lay together; the cock broods during the night; the hens take turns during the day, more, it would seem, to guard their common treasure from jackals and small beasts of prey than directly to forward the process of hatching, for that is often left wholly to the sun. Some thirty eggs are laid in the nest, and round it are scattered perhaps as many more, which are said to be used as food for the newly-hatched chicks.