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STUDIES AMONGrST AMCEBiE. 
By PROFESSOR P. MARTIN DUNCAN, F.R.S. 
President or the Geological Society of London. 
[PLATES Y. AND VI.] 
S HOULD a beginner in science wish to know what the very 
commonly repeated word Amoeba represents in nature, he 
will, of course, seek for information in the numerous deep and 
superficial works on natural history of the day. A glance at 
the drawings given in half-a-dozen books will convey the im- 
pression that this creature is remarkably given to change its 
shape, for no two are alike ; but unfortunately this unintentional 
truth is qualified by the fact that there is a singular want of 
conformity and unanimity in the written descriptions. Some 
naturalists will tell the inquirer that Amoeba is an animal; 
others that it is a plant ; and the very philosophical assert that 
it is neither, but that it belongs to the indefinite group of Pro- 
tista. There is, however, a general belief that it is an exceed- 
ingly minute piece of protoplasm, being the lowest form of 
living thing; that it is constantly changing its shape, and 
protruding from one part after another, long or lobed projections 
called pseudopodia, with which it catches its prey ; that any- 
thing over which it passes sinks in and is digested ; and that 
it contains a nucleus, a contractile vesicle, and some vacuoles. 
It is usually stated that there is an outer coat with a doubtful 
membrane on it, and a granular inner mass which never runs into 
the pseudopodia. Finally, it is said to cast off its legs and di- 
vide, the separate pieces turning to perfect Amoebae. The term 
64 amoeboid” is very constantly employed in explaining the move- 
ment, real or theoretical, of certain cells in the higher animals, 
and the idea is that it is a very slow, creeping, and changing one. 
Described as it is, and drawn as it has been, in the books 
by which the young naturalist has to be taught, can there be 
the least reason or necessity for asking, What is the Amoeba ? 
Suppose the matter be looked into a little more deeply. It will 
then be found that some very admirable observers are by no 
NEW SERIES, VOL. I. — NO. III. Q 
