THE PLANT WOKLD 111 



BRIEFER ARTICLES. 



Fossil Sequoias in North America. 



In a recent number of The Plant Wokld we published an article 

 showing how perilously near absolute extermination is the big tree 

 {Sequoia Washing toniana) of California. It is hardly necessary to say 

 that this and the redwood {S. semj'jervirens), are the only living repre- 

 sentatives of what was once a powerful and world-wide race of trees. 

 The genus Sequoia, represented by foliage, cones and wood, is very 

 widely distributed in a fossil state, many nominal species ha\dng been 

 described. Geologically it is found from the Jurassic to the Pleisto- 

 cene, and geographically from Japan, Asia, Europe, the Arctic regions, 

 including Greenland, and North and South America. 



In North America some 44 fossil forms have been described, of 

 which number about 35 are based on foliage and cones, and the remain- 

 der on wood showing internal structure of the Sequoia type. These are 

 found from our Lower Cretaceous to the present time, having been very 

 abundant in the Middle and Upper Cretaceous, and represented by a 

 considerable number throughout the Tertiary. It is probable, however, 

 that there has been more or less duplication in these species, for it is 

 often necessary to describe as different species foliage, cones and wood 

 that may have come from the same tree, because they have never been 

 found connected, and association in the same beds may or may not 

 argue identity. Occasionally a fossil is found "v\dth cones and foliage 

 attached, but usually they are separated. 



Both of the living types of Sequoia are abundantly represented 

 among these fossil forms. One of the most abundant and widely dis- 

 tributed is known as Sequoia Langsdorffii, and is of the S. sempervirens 

 type, while >S'. Coulfsiae represents the S. Waskingtoniana type, and is 

 about equally well distributed. A fine species known as S. magnifica 

 is found in the Yellowstone National Park. It had trunks fully ten 

 feet in diameter, and beautifully preserved wood of the S. sempervirens 

 type. — E. H. Knowlton. 



A Singular Tree. 



The photograph shoAvs the lower part of a slippery elm ( Ulmus 

 fulva). Wlien five and one-half inches in diameter it was stripjied of 

 its bark. On two sides the bark grew and raised the surface seven- 



