90 DR. BEALE, ON THE TISSUES. 



puscle, and the pus and mucoiis corpuscle, are composed 

 entirely of germinal matter, with a very thin layer of formed 

 material ; the viscid matter or mucus between the mucous 

 corpuscles is formed material. 



That the ' nucleus ' of an epithelial cell of mucous mem- 

 brane, or of the cuticle is germinal matter ; in a fully formed 

 ' cell ' the outer part, ^ cell-Avall and cell-contents ' consists of 

 formed material. 



That the ' cell- wall ' of a fat-cell or of a starch-holding- 

 cell informed material ; the ' nucleus ' of the former, and the 

 ' primordial utricle ' of the latter, are germinal matter ; while 

 the fat and the starch are the secondary deposits produced by 

 changes occui'ring in particles of germinal matter in the 

 central part of the mass. 



I have chosen the terms ' germinal matter ' and ' formed 

 material,^ because they serve to express the essentially differ- 

 ent nature of the two forms of matter of which every 

 elementary living structure is composed at the time it is 

 under observation. I do not think that it is possible for any 

 living particle to exist without being composed of matter in 

 these two states, — matter capable under favorable circum- 

 stances of producing germs from which new germs may be 

 developed infinitely, — and matter which once possessed this 

 power, but which has been formed or converted into a sub- 

 stance endowed with certain peculiar and important proper- 

 ties, it is true, but now totally destitute of the power of pro- 

 ducing matter like itself, reproduction, &c. 



It may be remarked that by the use of these terms alone, 

 the changes taking place in the development, growth, and 

 nutrition of tissues in health as well as in disease may be 

 described. I have endeavoured to study and describe actions 

 and changes rather than to give names and definitions to 

 structures which exist at any given period, but which are in 

 a state of constant though gradual and perhaps very slow 

 change. To aim at giving a history of the changes which 

 occur seems to me more likely to lead to useful results than 

 to attempt to define arbitrarily the limits of structures 

 between which there is in nature no observable line of de- 

 markation. In many cases the germinal matter passes 

 gradually into the formed material, and it would be impos- 

 sible to describe these by using the ordinary terms, — for 

 there are no means by which we could determine positively 

 which part of the structure was cell-wall, and which cell- 

 contents. I may, however, be permitted to say that I am 

 quite ready to modify the terms employed, in any way which 

 may be likely to render them more convenient or more useful. 



