240 



HUTCHINSON'S POPULAR BOTANY 



The first European discovery of the plant was made by Mr. C. J. Atkinson, 

 who forwarded specimens to the Botanical Museum at Cape Town, but 

 was otherwise rather reticent concerning the discovery. There was no 

 occasion for reticence. Welwitsckia mirabilis is an unique plant a mono- 

 typic genus, indeed totally unlike every other member of the Vegetable 

 Kingdom, both in appearance and mode of growth, and therefore a plant 

 to be taken account of. Fortunately, within a few years of its discovery, 

 the celebrated botanical traveller, Dr. Welwitsch, rediscovered it. While 

 exploring the waste and arid deserts of South- West Tropical Africa, not 

 far from Cape Negro, the doctor came upon a hard rough-looking disc, 

 elevated some ten or twelve inches from the ground, and having a diameter 



of from three to four feet. It was the 

 stem of a Tumboa. From deep grooves 

 in the circumference of the stem, two 

 opposite leaves tough, brown, and torn 

 into innumerable thongs hung down and 

 trailed, curling, along the sand to a distance 

 of five or six feet in both directions. These 

 were the true leaves.* It has since been 

 discovered that only two such leaves are 

 developed on every plant, and that they 

 persist during the long life of the indi- 

 vidual. The flowers which resemble the 

 cones of the Larch, spring up annually in 

 crimson clusters round the edge of the 

 disc, though the wood is of a stony 

 hardness. The concentric layers which 

 compose the stem show that growth in 

 thickness takes place as in dicotyledons : 

 but upward growth is arrested at an early 

 period. 



The age of many forest-trees is 

 enormous. The great Chestnut of Tort- 

 worth is believed to have been a flourishing young sapling in the time 

 of Egbert : an Oak in Normandy the chene chapeUe which was con- 

 verted into a chapel some two centuries ago, was probably at that time 

 seven hundred years old ; while the famous Salcey Oak is probably much 

 older than either, and the Winfarthing Oak (see fig. 244) on the Earl 

 of Albemarle's estate near Diss, in Norfolk, is perhaps more patriarchal 

 still. But the Methuselah of the race, according to Mr. W. Senior, is the 

 famous Greendale Oak at Welbeck. which is believed to have weathered 

 the storms of fifteen centuries. About a hundred and sixty years ago this 



* Not the cotyledons, as was at first supposed. Two cotyledons are, indeed, produced, 

 but they fall away while the plant is still quite young. 



FIG. 296. Ceropegia sandertioni. 



The flower of a climber whose srowing tip makes 

 circular movements in search of a support. 



