58 Prof. Asa Gray on Sequoia and its History. 



the swamps of the Atlantic coast from Maryland to Texas, 

 thence extending into Mexico : it is well known as one of the 

 largest trees of our Atlantic forest-district ; and although it 

 never (except perhaps in Mexico, and in rare instances) attains 

 the portliness of its western relatives, yet it may equal them 

 in longevity. The other relative is Glyptostrohus^ a sort of 

 modified Taxodium^ being about as much like our bald cypress 

 as one species of redwood is like the other. 



Now species of the same type, especially when few and the 

 type peculiar, are in a general way associated geographically, 

 i. e. inhabit the same country or (in a large sense) the same 

 region. "Where it is not so, wdiere near relatives are separated, 

 there is usually something to be explained. Here is an instance. 

 These four trees, sole representatives of their tribe, dwell almost 

 in three separate quarters of the world — the two redwoods in 

 California, the bald cypress in Atlantic North America, its near 

 relative, Olyptostrohus^ in China. 



It was not always so. In the tertiary period, the geological 

 botanists assure us, our own very Taxodium^ or bald cypress, 

 and a Glyptostrohus exceedingly like the present Chinese tree, 

 and more than one Sequoia coexisted in a fourth quarter of the 

 globe, viz. in Europe ! This brings up the question : Is it 

 possible to bridge over these fom* wide intervals of space and 

 the much vaster interval of time, so as to bring these extra- 

 ordinarily separated relatives into connexion? The evidence 

 which may be brought to bear upon this question is various 

 and widely scattered. I bespeak your patience while I en- 

 deavour to bring together in an abstract the most important 

 points of it. 



Some interesting facts may come out by comparing generally 

 the botany of the three remote regions, each of wliich is the 

 sole home of one of these three genera — i. e. Sequoia in Cali- 

 fornia, Taxodium in the Atlantic United States, and Glypto- 

 strohus in China, which compose the whole of the peculiar 

 tribe under consideration. 



Note then, first, that there is another set of three or four 

 peculiar trees, in this case of the yew family, which has just 

 the same peculiar distribution, and which therefore may have 

 the same explanation, whatever that explanation be. The 

 genus Torreya, which commemorates our botanical Nestor and 

 a former president of this association (Dr. Torrey), was founded 

 upon a tree rather lately discovered (that is, about thirty-five 

 years ago) in northern Florida. It is a noble yew-like tree 

 and very local, being known only for a few miles along the 

 shores of a single river. It seems as if it had somehow been 

 crowded down out of the Alleghanies into its present limited 



