DEGENERATION. 393 



from being in any way an abnormal phase of living action, it is seen 

 to be as natural a process for living beings to retrogress wholly, as 

 we have seen in some cases, or partly, in others as it is for them to 

 develop and advance. And what is thus undoubtedly true of the 

 individual man or other animal is no less so of the race. " Buried 

 civilizations" are by no means unknown ; extinct culture is an archaeo- 

 logical fact ; the decline and fall of nations are matters of history. May 

 not these things be likewise explained as a part of that wide theory 

 of life which regards even the highest interests of man as lying within 

 the operation and sway of causes which mold his f)hysical organiza- 

 tion ? If this notion be accepted, then is the idea of degeneration as 

 a normal phase of life rendered still more feasible and plain. Reach- 

 ing to the individual and to the species as well ; extending and includ- 

 ing in its scope the lowly organized as well as the higher being ; affect- 

 ing one group or class lightly, and influencing another wellnigh to the 

 complete exclusion of progress, we find degeneration and retrogression 

 to be numbered among the stern realities of existence. And no less 

 clearly and forcibly may we trace the truly natural place of degen- 

 eration in our own physical history : since, as physiology teaches and 

 daily experience declares, not an action is wrought or a thought con- 

 ceived without the presence of change and decay of tissue a process 

 this which, limited in early life by progressive growth and by devel- 

 opment, at last comes in our latter days to assume the reins of gov- 

 ernment, and in time to dissipate our energy and substance into the 

 nothingness of physical and corporate extinction. 



The philosophy of biology, however, may, in conclusion, be found 

 to point out to us that the subject of degeneration, while treating of 

 a powerful factor in modifying the living form, yet possesses a favor- 

 able aspect in relation to progress and evolution. High authority in 

 matters biological may be found for the statement that degeneration 

 is really a result of progress, that it is dependent on high development, 

 and that, while it simplifies the living being, " it produces the same 

 effect as differentiation, for it leads to variety in form." Thus there 

 is a kind of evolution and progress inseparable even from degeneration 

 itself. For the retrogression may in itself lead to variety and change, 

 and in due time such variety may be the starting-point of new and 

 higher developments. So, likewise, we are reminded that reduction 

 and degeneration of some parts may proceed contemporaneously with 

 the higher development of others, with the total result of perfecting 

 the organism and of evolving a higher type of structure. The degen- 

 eration of a frog's tail is in reality a feature of its higher type as com- 

 pared with its tailed friends, the newts and salamanders. The disap- 

 pearance and reduction of the tail which the young crab possesses is a 

 chief reason why we esteem the crab, whose body is all head and 

 chest, a higher animal than the lobster or prawn, with head, chest, and 

 tail complete. The degeneration of the " outside " gills of the Alpine 



