MICROBES AND PROTISTA. 5 
the English and German languages. In order to in- 
dicate the organisms which produce diseases, they 
make use of the word Bacteria, which is only the 
name of one of the peculiar species assigned to this 
group, and the one with which we have been longest 
acquainted. In this case, the name is generalized and 
applied to an entire group. : 
The Italian authors who have been recently occu- 
pied with the study of microbes have on their part 
adopted the name Protista, proposed by Heckel, and 
of which the sense, although not the etymology, is 
almost the same as that of the word microbe. 
In reply to the question whether there is any real 
advantage in establishing an intermediate kingdom 
of Protista between the two organic kingdoms of 
animals and plants, we must answer in the negative. 
This third organic kingdom only serves to render 
the structure of our modern classification more com- 
plex; and it includes, as may be seen from the list 
given above, a collection of very heterogeneous groups, 
which it would be more simple to leave in one or the 
other kingdom. We should, in our opinion, approxi- 
mate more closely to Nature’s plan by only admitting. 
two great kingdoms: the organic kingdom, which 
includes plants and animals; and the inorganic king- 
dom of minerals, The organic kingdom should then 
be divided into two. sub-kingdoms, animals and 
plants, of which microbes or protista, or whatever 
else they may be called, should form the connecting 
