288 PHYSIOGNOMY OF PLANTS. 



i. e. Nlapa-tree, more properly Muti-nlapa) as far as Lourenzo 

 Marques, almost to 26 of S. lat. Although Cadamosto said in the 

 15th century "erninentia non quadrat magnitudini," and although 

 Grolberry (Fragmens d'un Voyage en Afrique, t. ii. p. 92) found in 

 the " Vallee des deux Gragnacks" 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 re- 

 garded 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 Adan- 

 son and Perottet assign to the Adansonias measured by them an age 

 of from 5150 to 6000 years, which would make them cotempora- 

 neous 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 inqui- 

 ries, that of all European species of trees the yew is that which attains 

 the greatest age. He assigns to the yew (Taxus baccata) of Bra- 

 borne, in the county of Kent, thirty centuries; to the Scotch yew 

 of Fortingal, from twenty-five to twenty-six ; and to those of Crow- 

 hurst in Surrey, and Kipon 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 circum- 

 ference, and in which 815 annual rings have been counted." (End- 

 licher, Grundziige der Botanik, s. 399.) In the temperate zone of 

 the southern hemisphere, some species of Eucalyptus attain an enor- 



