THE FLORA OF THE EARLY MESOZOIC. 



183 



a height of 5,000 to 7,000 feet above sea-level, and are 

 much sought after by tourists as one of the wonders of 

 the country. Keports came to Europe concerning the 

 largest of them which were quite fabulous, but we have 

 received accurate accounts of them from Prof. Whitney. 

 The tallest tree measured by him has a height of 325 

 feet, and in the case of one of the trees the number of the 

 rings of growth indicated an age of about 1,300 years. 

 It had a girth of 50 to 60 feet. 



We know only two living species of Sequoia, both of 

 which are confined to California. The one (S. semper- 

 virens) is clothed with erect leaves, arranged in two rows, 

 very much like our yew-tree, and bears small, round 

 cones ; the other (S. gigantea) has smaller leaves, set 

 closely against the branches, giving the tree more the ap- 

 pearance of the cypress. The cones are egg-shaped, and 

 much larger. These two types are therefore sharply de- 

 fined. 



Both of these trees have an interesting history. If we 

 go back into the Tertiary, this same genus meets us with 

 a long array of species. Two of these species correspond 

 to those living at present : the 8. Langsdorfii to the S. 

 sempervirens, and the 8. Couttsm to the 8. gigantea.* 

 But, while the living species are confined to California, in 

 the Tertiary they are spread over several quarters of the 

 globe. 



Let us first consider the Sequoia Langsdorfii. This 

 was first discovered in the lignite of Wetterau, and was 

 described as Taxites langsdorfii. Heer found it in the 

 upper Ehone district, and there lay beside the twigs 

 the remains of a cone, which showed that the Taxites 

 Langsdorfii of Brongniart belonged to the Californian 

 genus Sequoia established by Endlicher. He afterward 



* 8. CouttsicB has leaves like 8. gigantea^ and cones like those of 8. 

 sempervirens. 



