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Organ containing the spores, and this reasoning is based prin- 
cipally upon the fact that the mycelium threads forming the so- 
called ascogon, and which terminate in the asci holding the spores, 
may be traced backward through the podetium or stem to the 
point of its insertion on the horizontal thallus below. Reinke 
claims with equal emphasis that the podetium is to be ranked as 
a thallus, that it forms no part of the fruit-body; he upholds his 
claim chiefly by the fact that it acts as an assimilating organ and 
therefore must be considered as a vegetative part of the plant and 
not a reproductive organ. The importance which Reinke attaches 
to his view of the morphology of the podetium explains perhaps 
the above-mentioned conclusion of some readers of the article 
that the two botanists are antagonistic in their views on the lichens. 
Their difference of opinion comes rather from a radical difference 
in their interpretation of morphological characteristics, and not 
from any real difference concerning the question at issue, viz: the 
place which the lichens ought to occupy in the natural system of 
classification. 
Regarding this point, Schwendener expressly says that he has 
No objection to the plan proposed by Reinke of classing the 
lichens as a group by themselves, but also states that he does not 
think this plan would entirely do away with the difficulties in 
question. He gives as an example of these difficulties the fact 
that there are several species of fungi belonging to one genus, 
Some of which live as parasites on algae, or as lichens, others are 
true fungi living entirely after the fashion of other plants of this 
Sroup. If the lichens are to be classed as a separate group, there 
must be some provision made for such plants as these, for it surely 
would not be logical to separate such closely allied forms by 
putting them in different groups. 
Reinke proposes not only a rearrangement by which the 
lichens would be restored to their original dignity of place, but 
also outlines a plan for classification within themselves based as 
nearly as possible upon what he considers phylogenetic principles. 
It may be noted in closing that it is a little curious and striking 
that this plan is founded upon the classification of Tuckerman, a 
botanist who attached little importance to the principles of 
Phylogeny in his treatment of the lichens. 
