H. BOTANY AND HORTICULTURE. 353 



rice may at any rate aflord similar esculent roots. The pro- 

 fessor, therefore, thinks the suggestion worth attending to; 

 and it is to be hoped that some one will try the experiment 

 as to the edible qualities of the plant in question. 4 Z>, Au- 

 fjust 3, 1872, 151. 



THE SEQUOIAS OF CALIFORNIA, AXD THEIR HISTORY. 



Dr. Gray's address before the American Association at its 

 last meeting, recently republished with supplementary notes 

 and ajjpendix, discusses certain scientific questions suggested 

 by a visit to the "Big Trees" of California. More remark- 

 able than either the size or age of these trees (and none of 

 them is over two thousand years old) is their isolation. The 

 only existing species of the genus are restricted to limited 

 portions of California, one to the Coast Range, the other yet 

 more narrowly to a few spots in the Sierras. Were they 

 created thus isolated both systematically and geographically? 

 are they destined to a more extended range ? or are they but 

 the scanty remnants of a race now almost extinct ? The first 

 suppositions are shown to be as improbable as unscientific. 

 The third forms the main subject of the address. 



The only near relatives of the red-woods are our Southern 

 cypress, ranging from Maryland to Mexico, and the Glypto- 

 strohus, which is found in China. Yet geology teaches that 

 in the tertiary period these families were not thus separated, 

 but that the cypress, several Sequoias, and a Glyptostrohus 

 existed together in Europe. To show the connection of these 

 facts, a comparison is made of the present floras of the three 

 regions. Eastern and Western America and Northeastern 

 Asia. It is found that while there is very great dissimilarit}'" 

 between the characteristic forms of the Atlantic States and 

 California, there is ^s remarkable a likeness between the vesf- 

 etation of the same states and Eastern Asia. Various in- 

 stances are cited of plants of very limited range in the At- 

 lantic States, which occur again, the same or nearly so, in 

 Japan or Eastern Asia, and nowhere else. And of all the 

 numerous species which are common to these regions, either 

 identical or with slight diff'erences, only one third are also 

 found on the intermediate Pacific slope of America, and of 

 the corresponding genera less than one fourth. 



Now the only known cause of resemblance is inheritance 



