ORIGIN OF DISEASE AND THE GERM THEORY. 141 



mind that there is always a tendency for the constituent por- 

 tions of higher organisms to dispense, in a greater or less degree, 

 with the honds which combine them, however well knit together 

 the different parts may be. 



Furthermore, there is the still greater danger always to be 

 apprehended that these bonds themselves, among which the 

 most important are the vascular and the nervous mechanisms,, 

 may be more or less completely rent asunder in any particular 

 part, or in many different ways interfered with in regard to their 

 efiBciency. With these few words by way of prelude to the con- 

 siderations which follow, we now propose to give an account, 

 firstly, of some structural points bearing upon the question of 

 evolution in disease, after which we shall discuss some func- 

 tional aspects of that subject, and then conclude with a brief 

 reconsideration of the more general points of view. Before 

 continuing, however, I must here acknowledge the copious use 

 of a work written some time ago by my brother, Dr. D. Astley 

 Gresswell. 



We now proceed to discuss ** Some abnormal Structural Mani- 

 festations which point to the, idea of Evolution." 



Speaking generally, it is, as a matter of fact, found that by 

 various plants and animals most of the substances known as 

 carbo-hydrates, i.e. starches and sugars, are convertible into- 

 one another, that fats and some of the carbo-hydrates are 

 mutually convertible, and that albuminates, such as white of 

 egg, can be split up into fats and other bodies. Among 

 lowly-developed creatures albuminous infiltration is general, and 

 it also occurs in higher organisms. Albuminous infiltration, 

 fatty infiltration, and fatty and pigmentary degeneration mani- 

 fest themselves in lower organisms, and are also seen in higher 

 organisms, both as phases of nutrition and, moreover, also as 

 abnormal or reversional phenomena. 



Glancing for a brief space at the lowest forms of life which 

 lare known to us, we observe that they multiply either by split- 

 ting into two or more independent parts, or by a very closely 

 allied process, viz. the budding-off of portions which gradually 

 increase in size, both before and after they are set free. Re- 

 generation seems to be the more active the younger the indi- 

 vidual, and also the lower in the scale of life it may be. It 

 is said that the ova of higher animals may divide, and that 



