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They are all confined to North America. The third one, not in 

 the Garden, is the Montezuma Cypress of Mexico, Taxodium 

 mucronaium. The leaves of the last-named tree may be deciduous, 

 semi-evergreen or evergreen according to situation. Evergreenness 

 is induced, naturally, by optimum conditions. This tree was long 

 reverenced by the Indians before the discovery of America by 

 Europeans. It is not hardy, though occasionally planted in Cali- 

 fornia. It is interesting, since it may attain a height of 170 feet 

 with a trunk 40 feet in diameter. A certain very large tree of this 

 kind in Mexico City has been regarded as possibly the oldest living 

 tree in the world, rivaling the Redwoods of California. Our native 

 Bald Cypress may commonly be found 400 to 600 years of age 

 and occasionally from 720 to 1200 years. It is remarkable that 

 trees living in such wet situations should attain such age. 



Some botanists regard all these trees as varieties of one species. 

 The differences, it is said, are more geographical than botanical. 

 The Pond Cypress, it is claimed, is the result of less fertile condi- 

 tions. It is usually confined to the prairies and low pinelands and 

 may even occur on sand dunes. The peculiar appressed nature of 

 the leaves clinging close to the twigs may, consequently, be an 

 adaptation to prevent excessive evaporation of moisture under 

 these drier conditions. The Bald or River Cypress, on the other 

 hand, demands wetter situations. Occasionally both types of 

 leaves, the wide spreading and the closely pressed, are found on 

 the same tree. 



One or two very similar trees are found in China and are known 

 as Glyptostrobus heterophyllus. This is little known in cultivation 

 outside of China and is unknown in the wild state. Several speci- 

 mens have been cultivated at the Garden in the conservatories. 

 Very commonly, however, this relatively rare plant is regarded as 

 a Taxodium. It resembles the Bald Cypress very closely but it 

 loses its cone scales rather than retaining them as in the native 

 trees. This is the principal basis of distinction, similar to that be- 

 tween the Douglas Fir and true firs. Fossil relatives of both 

 Glyptostrobus and Taxodium have been found from widely sepa- 

 rated regions. 



