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Various

"Scientific American Supplement, No. 324, March 18, 1882"

The complete dependence
of the evolution of oxygen upon the presence of algae, and its complete
independence of the pigment proper to the animal, were still further
demonstrated by exposing as many as possible of those anemones known
to contain yellow cells (_Aiptasia chamaeleon, Helianthus troglodytes_,
etc.) side by side with a large number of forms from which these are
absent (_Actinia mesembryanthemum, Sagastia parasitica, Cerianthus_,
etc.). The former never failed to yield abundant gas rich in oxygen,
while in the latter series not a single bubble ever appeared.
Thus, then, the coloring matter described as chlorophyl by Lankester
has really been mainly derived from that of the endodermal algae of the
variety _plumosa_, which predominates at Naples; while the anthea-green
of Krukenberg must mainly consist of the green pigment of the ectoderm,
since the Trieste variety evidently does not contain algae in any great
quantity. But since the Naples variety contains a certain amount of
ordinary green pigment, and since the Trieste variety is tolerably sure
to contain some algae, both spectroscopists have been operating on a
mixture of two wholly distinct pigments--diatom-yellow and anthea-green.


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