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Show 288 PHYSIOGNOMY OF PLANTS. i. e. Nlapa-trce, more properly Muti-nlapa) as far as Lourenzo Marques, almost to 26° of S.lat. Although Cadamosto said in the 15th century 11 eminentia non quadrat magnitudini," and although Golberry (Fragmens d'un Voyage en Afrique, t. ii. p. 92) found in the "Vallee des deux Gagnacks" trunks which, with 36 English feet diameter near the roots, were only 64 English feet high, yet this great disproportion between height and thickness must not be regarded as general. The learned traveller Peters remarks, that "very old trees lose height by the gradual decay of the top, while they continue to increase in girth. On the east coast of Africa one sees not unfrequently trunks of little more than ten feet diameter, reach a height of 69 English feet." If, according to what has been said, the bold estimations of Adanson and Perottet assign to the Adansonias measured by them an age of from 5150 to 6000 years, which would make them cotemporaneous with the epoch of the building of the Pyramids or even with that of Menes, a period when the constellation of the Southern Cross was still visible in Northern Germany (Cosmos, bd. iii. s. 402 and 487; Eng. ed. p. 293, and note 146), on the other hand, the more secure estimations made from the annual rings of trees in our northern temperate zone, and from the ratio which has been found to subsist between the thickness of the layer of wood and the time of growth, give us shorter periods. Decandolle finds as the result of his inquiries, that of all European species of trees the yew is that which attains the greatest age. He assigns to the yew (Taxus baccata) of Braborne, in the county of Kent, thirty centuries; to the Scotch yew of Fortingal, from twenty-five to twenty-six; and to those of Crowhurst in Surrey, and Ripon in Yorkshire, respectively, fourteen and a half and twelve centuries. (Decandolle, de la longevite des arbres, p. 65.) Endlicher remarks that the age of another yew tree, in the churchyard of Grasford, in North Wales, which measures 52 English feet in circumference below the branches, is estimated at 1400 years, and that of a yew in Derbyshire at 2096 years. In Lithuania, lime trees have been cut down which were 87 English feet in circumference, and in which 815 annual rings have been counted. (Endlicher, Grundziige der Botanik, s. 399.) In the temperate zone of the southern hemisphere, some species of Eucalyptus attain an enor- |