1 1 6 PRO DUG TION OF 



scale of organization, may give rise to forms of bio- 

 plasm approximating more and more closely to the 

 lowest constant forms of life with which we are 

 acquainted. A doctrine asserting that by continual 

 retrogression through ages, the descendants of the 

 highest forms would gradually deteriorate until their 

 only remaining representatives were monads, would 

 not be very easily disproved, and might be supported 

 by many ingenious arguments. It is a view that 

 doubtless would recommend itself to many minds in 

 the present day. 



But on the other hand it is obvious that cells and 

 organisms might retrograde and produce various 

 modified forms, without giving rise to any of those 

 particular forms characteristic of the lower organisms 

 which we are acquainted with. Nay, cells of different 

 organisms might give rise to many different retrograde 

 forms, and every one of these be very different from 

 one another, and yet totally unlike any known or- 

 ganism. It is obviously possible that there should be 

 infinite advance and infinite retrogression in multi- 

 tudes of parallel lines, as it were, without the resulting 

 forms of any one line becoming identical with those 

 of another. Just as it is possible to conceive infinite 

 advance in the features of the dog, without any 

 resemblance whatever to the human face resulting, 

 and retrogression and deterioration of the latter pro- 

 ceeding to any degree, and continuing for any length 

 of time, without the production of the simian type of 

 countenance. 



