66 MISSOURI BOTANICAL GARDEN. 
If one considers the manner in which a fungus disease 
attacks plants at the present day, one will find that closely 
related plants are apt to be afflicted by the same disease. 
Thus Plasmopara Cubensis grows on a large number of 
genera of the Cucurbitaceae ; Gymnosporangium Nidus Avis 
(Aecidium) on several genera of the Pomeae (Rosaceae) ; 
Trametes Pini on several genera of the Coniferae, and so 
on. Judging by analogy, one might expect genera nearly 
related to Taxodium to be diseased similarly to Taxodium. 
There are but a few genera, closely related to Taxodium, 
which grow at the present time. In North America: 
Taxodium mucronatum is found in Mexico; Sequoia 
gigantea and S. sempervirens, in California; Libocedrus 
decurrens, in California and Oregon; and the less closely 
related species of Juniperus. In addition to these there 
are a number of other species scattered over the globe, 
thus Libocedrus Douiana and L. Bidwillii in New 
Zealand, Libocedrus cupressoides and L. Chilensis in 
Chili, also a dwarf species in Iceland. A closely related 
tree, Glyptostrobus Huropaeus, is found in some of the 
southeastern provinces of China. All of these trees were 
common over the whole earth in Tertiary times, and if a 
disease was common to them then, one might expect to find 
that to-day. Of the species enumerated, the Sequoias are 
apparently free from diseases of the wood * while Libocedrus 
decurrens and the species of Juniperus so far seen, are affected 
by diseases which cause local rotting of the wood much like 
that of the cypress. Of the other trees nothing is known 
so far. The fungus which causes the decay in Libocedrus 
is described in the following, while that found in the trunks 
of Juniperus species is to be described in a separate paper 
soon to appear. 
* Sargent, C.S. Silva of North America 103.140. 1896. 
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