where he cuts it off. When the tree has so grown that this denuded ring is five or six feet above the ground, some one of the next generation repeats the process, and the tree grows up, leaving the scars of these successive injuries. Some trees bear the marks of nine or ten successive strippings, extending half way up the trunk, and forming a series of complete circles or rings around it, frequently projecting so far from the actual level of the trunk as to enable a person to walk round it by holding on to the one above.

The colour of this fibrous bark is mostly of a neutral grey, but a thin outer bark is seen on some trees, of a red or copper colour, which at first is quite smooth, but afterwards splits and curls off, showing the green bark underneath. This splitting of the outer bark gives to the trunk a rough, uncouth appearance. Very strong ropes and nets for catching antelopes are made from the bark.

The fruit of the Baobab is an oblong or oval woody capsule, and hangs from the branches at the end of a long stalk. It frequently measures from twelve to eighteen inches long, and six inches or more across. It is covered with a greenish soft down, and internally it is divided into eight or ten cells. The seeds are numerous, and are imbedded in a pulpy substance, which has a pleasant acid flavour, and when dry is easily pulverized. In Cairo, this is constantly done, and the powder is used for medicinal purposes. In its fresh state the pulp is eaten by the natives, and elephants are said to be exceedingly fond of it. In Central Africa, a regular dish is made from it, by beating it up with water to the consistency of a thin paste, which is eaten by dipping in the forefinger, and then sucking it. In some parts, the juice is expressed from the pulp, and is much valued as a medicine in cases of fever. The woody capsules, after the pulp and seeds have been carefully removed, make excellent vessels for holding water, etc. They are also reduced to ashes, which, along with the ashes of the bark, is boiled in palm oil for use as soap. The leaves, which are palmate, giving rise to the specific name, digitata, are occasionally used by the natives for covering their huts; while on the eastern coast of Africa they are carefully dried, and reduced to a powder, which they daily mix with their food, and which has the effect of diminishing the excess of perspiration occasioned by the heat of the climate.

The wood, as we have before said, is exceedingly soft and porous, and it is very liable to the attacks of fungi, and this is said. to be particularly the case in Eastern Africa. When so attacked, the wood, of course, soon decays, so that the trunks are very easily hollowed out, and within them the dead bodies of such as are

refused the rite of burial are suspended. They soon become dry, and require no process of embalming. During the progress of the Livingstone expedition, an amusing incident occurred, illustrating the rapidity with which the wood absorbs moisture. In crossing the Lua, a tributary of the Zambesi, one of the party made a large float of thoroughly dry Baobab-wood for the purpose of floating himself across. Before being used it was lighter than cork, but it absorbed the water so quickly, that the unlucky inventor was glad to make all possible haste to shore. It is said that in Abyssinia the wild bees perforate the trunks, lodging the honey in the holes; and this honey is considered the best in the country.

Considering the softness of the wood, it seems surprising how the immense weight of the spreading foliage and heavy woody fruits is supported. Nature, however, appears to have provided bulk of stem to make up for loss of strength; and it is also a remarkable fact, that when the foliage on a particular branch increases so much as to become too heavy for it, the branch itself also increases in thickness. Not, however, equally throughout its circumference, but in a vertical direction, so that the new wood is formed precisely in the position where the greatest strength is required.

The flowers of the Baobab are borne on footstalks four to six inches long. The calyx is very large, and cup-shaped, green on the outside, and covered with short soft hairs. Inside it is of a pale colour, and has a silky appearance. The petals are of a cream white colour, and when the flower is fully expanded, are turned back over the calyx. The stamens are united into a long, thick tube, terminating in numerous filaments, each bearing a one-celled anther of a golden yellow colour. The pistil projects through the stamen tube, hanging down a considerable distance, and terminated by a stigma divided into seven spreading pubescent rays. The tree is deciduous, putting forth its dark green leaves towards the end of our autumn. The flower-buds, however, which in the distance look like small green balls, an inch or more in diameter, begin to open before the young foliage becomes conspicuous, and continues in bloom, while the foliage increases so, that the dark green of the leaves and the cream-white of the flowers offer a pleasant contrast. The appearance of these flowers, when fully expanded, is very beautiful. They frequently measure six inches across. It is no uncommon thing to see the fruits of the past season hanging upon the trees when they are again in flower. Frequently they cannot be got at, owing to the danger of climbing

amongst branches of so soft a wood; or it may be that they are so sheltered by the ramifications of the branches, that the natives are unable to strike them off with the sticks which they throw into the trees for that purpose. The woodcut represents a branch with an old fruit of the past season, a flower-bud, and an expanded flower.

The coloured plate is a reduced copy of a painting, made by Mr. Baines during a boat voyage from Tette to the Kongone mouth of the Zambesi delta, in 1859. From what we have said of the African Baobab, together with the assistance of the plate, we hope that its peculiar form and habits will be understood, and an interest created in its relative in Australia, to which we shall devote our next paper.

IRREGULARITIES OF STRUCTURE IN FISHES.

BY JONATHAN COUCH, F.L.S., C.M.Z.S., ETC.

THERE is no class of organized creatures that is not liable to some degree of variation in structure from what may be termed its natural type; which may be as regards an excess in the number of the organs, or of their deficiency of development; to which may be added some alteration of shape in the body itself, either as concealed within or prominently on the outside. Variations equivalent to these are common also among vegetables; and this more especially when they have been under the influence of human agency; but in the latter instances we are often able to trace the circumstance to some scarcely obscure cause; and not seldom it has been effected by the skill of the cultivator. But in animals, and even such as are beyond human control, while changes in the normal structure have been of not unfrequent occurrence, and the facts have excited wonder even among the students of nature, and have even stirred up the spirit of superstition in the seemingly devout, no clue to the influencing cause has been hitherto obtained. The subject therefore remains in doubt, although some of the higher interests of the community are mingled with it; for the human race is not less liable to afflictive and untoward malformations than are the creatures which inhabit the woods and waves, or have been rendered submissive to man's domestic control.

In the human race there are many abnormal variations of structure that when brought to the birth are hidden from sight; and many also are the instances of arrested or unnatural development -perhaps of internal organs-which have been the cause of abortion. in an early stage of pregnancy, by fatally interfering with the further growth and development of the embryo. It may be that this is less frequent in animals that are altogether wild, and thus beyond the influence of changing and artificial causes; but that it may occur even among the inhabitants of the ocean will appear from the many instances I shall relate, but in which the irregularity of structure has not been so great as to render the subject of it incapable of obtaining subsistence, and of escaping from the pursuit of enemies, of which the number is greater and the ferocity more intense than among the inhabitants of the land; but that there are many which from deficiency of structure are not capable of successful effort to escape, and perhaps of successfully seeking after food, will appear

from close observation to be highly probable. I have supposed, from extensive inquiry, that in the great family of chondropterygian or what are termed cartilaginous fishes, there is less liability to abnormal formation than in what are termed the bony or malacopterygious kinds; and yet in the former class the common picked dog has been found with two distinct heads, which were joined, at what might be called the neck, to a single body. This little creature could scarcely have lived beyond its birth in the sea; but circumstances forbade the trial of its capacity for a separate existence, and its appearance into light took place on board the fisherman's boat; by which accident this remarkable example of the vagaries of nature was preserved to be gazed at as an object of curiosity.

A very young trout has also been seen, with an effort at the development of a second head; which, however, was much less complete than in the instance of the picked dog. That a somewhat similar formation may be met with in even a higher class of animals, with also a much more extensive condition of development, I have witnessed in the instance of a viper; of which it was the more remarkable that two individuals were met with in the same district, with the interval of only a year or two; and of which the supposition may be hazarded, that both were the progeny of the same parent.

As it is intended that our observations shall for the most part be confined to the inhabitants of the sea, I only remark of this instance of a viper with two heads, that when found it had obtained about the fourth part of the adult growth; but as a viper rarely takes its food in captivity it could not be discerned whether it was with one or both of its mouths that food was taken. The heads were separate to a small distance down the neck, and the one that was on the right was in a small degree the largest. They often moved separately, and at times in different directions. The tongues were thrust out independently of each other; but when a particular object excited attention both of the heads were directed towards it, and they moved forward together.

By the side of these remarkable instances of a double development of the head and neck-in a fish and serpent-I place an instance of the doubling of the vertebra in an opposite direction; which was met with in the mud lamprey (Ammocætes branchialis), of which the following is a description. It had attained to a little more than half the usual size of this fish; and the division of the body into two portions was at about the position of the vent, where both the portions became bent down from the straight direction.