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agreed that it might be possible that they come from the cytoplasm, but 
that they finally lie in the vacuole. He believed the principal constituent 
of the bodies to be a fatty oil, since their contents dissolve in alcohol, 
benzol, ether, etc. In addition to the fatty oil, some other material was 
found to be present, appearing as a residue after the solution of the oil. 
The membrane which he observed surrounding the bodies after they had 
been stained with iodine and with cochineal, was apparently composed of 
some protein material, insoluble in dilute acid and in alkalies. Since the 
bodies were unchanged after a three-months' cultivation of the plants in 
darkness, and since they were still present, in such cases, in the very young 
cells, just as in the plants which had grown in the light, he concluded that 
they have no significance in nutrition and that they are merely products of 
excretion. 
Wakker ('88) included the oil bodies of the liverworts under the "elaio- 
plasts," as he had named the oil-producing bodies which he had demon- 
strated in many phanerogams. Although these bodies appear, in life, to 
lie in the cell sap, Wakker showed by abnormal plasmolyosis that they, in 
reality, lie in the cytoplasm. He believed them analogous to leucoplasts 
and chloroplasts, holding that they multiply by division and are distributed 
to the daughter cells in mitosis. 
Von Kiister ( '94) believes that the oil bodies are formed from a protein 
"stroma" and that the apparent membrane seen in fixed material is an 
artefact. Since he was not able to see the membrane in living material, 
even with the strongest magnification, he considered it a precipitation 
membrane, formed by the interaction of the oil and the substance of the 
stroma. He showed that the membranes were not visible in material which 
had been fixed in osmic acid and stained with gentian violet. He also 
showed that a double membrane could be formed by the use of dilute 
alcohol, followed by strong. In regard to the nature of the bodies, he 
believed with Pfeffer that they are excretion products. He did not believe 
that the oil bodies undergo division and are handed down from cell to cell, 
but thought that they are newly formed in each cell. 
Garjeanne ('03) believes that it is possible to show that the oil bodies 
are in reality merely vacuoles filled with oil which is secreted from their 
walls; that they lie in a half-fluid transition substance; that they increase 
by division, and that the membrane is an artefact. He admits, however, 
that the picric acid which he used in his demonstrations acts very rapidly, 
so that observations upon young cells must be made within one minute 
after the application of the acid, before disorganization of the cell contents 
sets in. He compares the oil bodies to the leucoplasts in their origin from 
Anlagen, which he believes to be vacuoles in the case of the leucoplasts also. 
After being fully formed, the oil bodies, he says, are no longer capable of 
division, remaining thereafter unchanged. In addition to the vacuoles, or 
Anlagen, of the oil bodies, he describes other minute structures which are 
