244 
ORGANIC DEATH. 
Nov., 1890. 
or generally, the same kind of relation to each other, it will 
go far to prove that the controlling force is an internal rather 
than an external one, because the almost infinite diversity of 
external influences makes it inconceivable that there should 
be any constant analogy among schemes of change moulded 
by those external influences alone. 
Now, if we consider the scheme of change in an individual, 
whether animal or vegetable, we may observe among a vast 
number of details four leading factors. Let us take an 
individual of one of the higher orders, a vertebrate, or a 
phanerogam, in which all these four factors are distinctly 
exhibited. Every such individual is at the beginning simple 
in structure, soft and cellular in substance. This is the first 
stage of its development. In a very short time solidification 
of certain parts commences, with increase of size up to a 
definite point. This is the second stage. Meanwhile the 
muscular, fibrous, contractile tissues have been attaching 
themselves to these solidifying parts, and slowly developing ; 
but they do not reach their full maturity, their greatest 
tenacity and elasticity, until some time after the cessation of 
growth. When they reach that maturity the third stage of 
development is accomplished. Tne fourth stage consists in 
the maturing of the great nervous system, the organs of 
sensation, perception, thought, and passion, which do not 
reach their climax till late in life, when all the other factors 
are beginning to decline. The maturity of the nervous 
system is soon followed by decay of power and the inevitable 
death. 
This is the sequence of change in all individual life. 
First, the cellular stage. Second, the osseous stage. Third, 
the fibrous stage. Fourth, the nervous stage, and then 
dissolution. 
I have taken the names of these stages from the animal 
world as being the higher in rank and showing the charac¬ 
teristics of each more completely. The corresponding stages 
in the vegetable world are:—First, the cellular, which is 
similar in both. Second, the woody stage. Third, the leaf 
stage, with its attachments to the solid framework, and its 
traces of contractile power. Fourth, the blossom stage, with 
its concentrated energy and marvellous powers of adaptation, 
suggesting an approach to instinct. 
Can any such sequence of change be traced in the develop¬ 
ment of species, genera, and orders ? 
It may easily be understood that to trace the sequence of 
change in any species must be extremely difficult. In the first 
place the bservations of cientific men do not extend over a 
