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1903] GAMETOPHYTES AND EMBRYO OF TAXODIUM 129 
Taxus (Jager, ’99) and Cephalotaxus (Arnoldi, ’00) there are 
more than eight free nuclei present before cell formation, and 
the tiers are not so definite as in Taxodium. In the Cupresseae 
(Strasburger, ’72) the tiers are at first composed of single cells, 
while in the Abieteae only one tier is first formed which then 
gives rise to four by successive divisions. Coulter (’97) and 
Coulter and Chamberlain (’o1) have described peculiarities in 
the number of embryos formed from one archegonium, and in 
the relation of suspensors to embryos in Pinus Laricio, which are 
not unlike the diversities found in Taxodium. 
SYSTEMATIC. POSITION OF TAXODIUM. 
The family Taxodieae as arranged by Eichler is acknowl- 
edged a tentative one, and when we compare the gametophytes 
of Sequoia and Taxodium, the only two genera of this family in 
which this part of the life history has been followed, we are 
impressed, not with similarities, but with divergencies; and it 
becomes at once apparent that, if gametophytic characters are of 
any consequence in classification, the group as it now stands is 
an artificial one and must be rearranged. The points of diver- 
gence between Taxodium and Sequoia are so striking that to 
retain them longer in the same group would do violence to 
taxonomic principles. In the large number of functional mega- 
spores and prothallia present in its sporangia Sequoia is markedly 
primitive, and in the arrangement and number of its archegonia 
it is, so far as known, sui generis. Its male gametophyte is 
imperfectly known, the young stages being quite unstudied. 
In the preceding pages attention has been called in passing 
to certain of the more evident structural similarities between 
Taxodium and the Cupresseae, and for the sake of brevity they 
will not again be rehearsed here. It is sufficient to say that 
Taxodium agrees with the Cupresseae in all gametophytic charac- 
ters that seem to me of much taxonomic importance, and I think 
it evident that such essential agreement with the Cupresseae on 
the one hand and such fundamental divergence from m Sequoia on 
the other must necessitate the removal of Taxodium from its 
connection with the latter and its insertion in the former family. 
