72 THE HISTORY OF CREATION, 
which have developed independently of one another and 
independently of the animal and the vegetable kingdoms. 
Even if we adopt the monophyletic hypothesis of descent, and . 
maintain a common origin from a single form of Moneron for 
all organisms, without exception, which ever have lived and 
still live upon the earth, even in this case the connection 
of the neutral Protista on the one hand with the vegetable 
kingdom, and on the other hand with the animal 
kingdom, must be considered as very vague. We must 
regard them (compare p. 74) as lower offshoots which have 
developed directly out of the root of the great double- 
branched organic pedigree, or perhaps out of the lowest tribe 
of Protista, which may be supposed to have shot up midway 
between the two diverging high and vigorous trunks of the 
animal and vegetable kingdoms. The individual classes of 
the Protista, whether they are more closely connected at 
their roots in groups, or only form a loose bunch of root off- 
sets, must in this case be regarded as having nothing to do 
either with the diverging groups of organisms belonging to 
the animal kingdom on the right, or to the vegetable kingdom 
on the left. They must be supposed to have retained the 
original simple character of the common primeval living 
thing more than have genuine animals and genuine plants. 
But if we adopt the polyphyletic hypothesis of descent, 
we have to imagine a number of organic tribes, or phyla, 
which all shoot up by spontaneous generation out of the 
same ground, by the side of and independent of one 
another. (Compare p. 75.) In that case numbers of dif- 
ferent Monera must have arisen by spontaneous generation 
whose differences would depend only upon slight, to us 
imperceptible, differences in their chemical composition, and 
