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 As ordinarily seen in cultivation it is a small tree of slow growth, and is quite distinct from the Chinese Glyptostrobus heterophyllus, with which it has been occasionally confused.

3. Var. mucronatum.

This differs from the type in the foliage being more persistent, generally lasting two years on the tree, and in the time of flowering, which is in autumn. The panicles of male flowers are generally more elongated than those of the United States tree. The leaves are usually shorter, lighter green in colour, and blunter at the apex.

These differences scarcely entitle this form, which occurs in Mexico, to separate specific rank. Specimens of the type, occurring at high elevations (1600 to 2000 feet) in Texas, approach it in character of the foliage; and in some Florida specimens the panicles of flowers are as large as any occurring on Mexican trees. The cones vary greatly in size and form in trees of Taxodium, occurring both in Mexico and the United States. Sargent, who has seen the tree in Mexico, was unable to distinguish it, by either foliage or habit, from the type.

It is evidently a geographical form in which certain differences of foliage have been brought about by climatic influence. One is led by a study of the specimens from many different regions to see in Taxodium a single species very variable in the wild state, rather than a number of distinct species.

Taxodium does not produce knees, so far as we can learn, in Mexico, where trees generally stand upon dry ground. According to Seeman, the tree is known in Mexico as Sabino, and is diffused over the whole tableland of that country. There are reported to be extensive forests of it at altitudes varying from 4500 to 7500 feet. Concerning, however, the character and distribution of these forests our information is very scanty. Much more is known about the remarkable isolated examples of very old and enormous trees, which have always attracted the attention of travellers in Mexico. The most noted of these is the tree of Santa Maria del Tula, about eighteen miles south-east of the city of Oaxaca, which was measured by Baron Thielmann in 1886, when its height was between 160 and 170 feet. Its