6\ Beer. — On Elaioplasts. 
the species of Gagea are said by Raciborski to possess a somewhat different 
structure. In these plants the spherical elaioplasts are characterized by the 
feeble development of the stroma ; they are surrounded by a plasmatic 
envelope and contain within this an oily substance like that found in other 
elaioplasts. The micro-chemical observations of Wakker and Zimmermann 
have shown that the elaioplasts consist of a plasmatic matrix or stroma in 
which are embedded numerous minute oil drops. Zimmermann points out 
that these oil drops show a close similarity in their reactions with the oil 
drops obtained from plastids. 
The origin of the elaioplasts has been very little studied. Raciborski 
states that in Ornithogaliim umbellatum they arise as small, highly refractive 
spherules which always lie at one pole of the usually elongated cell-nucleus. 
Although Wakker had no material with which to work out the 
development of the elaioplast, he ventures an interesting suggestion at 
the conclusion of his account of the oil-bodies of liverworts. ‘ Leider ist 
durch diese Mittheilung der Ursprung der Elaioplasten nicht ausgemacht, 
es ist mir aber ausserst wahrscheinlich, dass es bei den Lebermoosen meta- 
morphosirte Chlorophyllkorner sind. Vielleicht ist dieses auch bei Vanilla 
der Fall.’ 
Garjeanne’s work (5) on the oil-bodies of the Jungermanniales clearly 
indicates that these bodies have a different origin to that suggested by 
Wakker ; my own observations on elaioplasts recorded below will; however, 
show that his guess was nearer the truth in the case of some Phanerogamic 
elaioplasts. 
The function of the elaioplast is quite unknown. Wakker believed 
that they might be oil-formers much as leucoplasts are starch-formers. 
Zimmermann offered the suggestion that they might prove to be parasitic 
or symbiotic fungi living within the cells of the higher plant. 
Raciborski, however, considers them to be normal organs of the cell 
in which they occur, and classes them with oil-bodies, tannin-vesicles, and 
ordinary vacuoles. 
In the liverworts oil-bodies have been known to occur since the time 
of Gottsche, and even earlier. The first really fundamental description of 
these bodies is due to Pfeffer (4), and quite recently their development has 
been fully worked out by Garjeanne (5). Oil or fat bodies of a somewhat 
similar appearance to those of the liverworts have been described by 
Radlkofer (6 and 7), Monteverde (8), Solereder (9), and others, in the tissues 
of a number of Dicotyledons and Monocotyledons. Opinion varies very 
much as to the relation of these oil-bodies of liverworts and Phanerogams 
to the elaioplasts. Some believe the two structures to be closely allied, 
whilst others are of opinion that they are radically different from one 
another. 
From this brief survey of the literature it will be seen that elaioplasts, 
