Members of the Aquatic Salamander. 95 



self with one or two general observations. The process of growth 

 naturally leads us to consider the more general law of organization, 

 from whence it would seem to emanate ; I mean, the formation of 

 structures, or tissues, through the intermediate agency of that 

 substance, which we call coagulable lymph. Indeed, it would 

 seem that this matter is the matrix of every structure. It is 

 the simplest form of animal existence, and it is the first state of 

 existence of even the most perfect animals. It is the medium 

 through which every breach of continuity is united,*and through 

 which every loss of substance is restored. And although it is 

 only on such occasions that its existence and importance is deve- 

 loped to us, there is good reason to believe that it constantly exists 

 as a separate and independent part in all animals, in a greater or 

 less degree, and that it is through its means that the whole process 

 of nutrition is carried on. As forming a part of animals it bears 

 always a certain proportion to the others, being inversely as their 

 state of perfection, and in the simplest of them as in the animal- 

 culee of the sponge it appears to be the sole and only one. 



The knowledge we possess of this substance we entirely owe 

 to Mr. Hunter, an obligation, which, together with his views of 

 inflammation, I hold to have as high claims ou the gratitude of 

 society as any discovery which has ever extended the power of 

 human art over the functions of animal life. 



This matter in its physical properties has been considered as a 

 peculiar kind of animal gluten, similar in the opinion of many, 

 and the same in the opinion of a few, as the fibrine of the blood. 

 As regards its vital properties it is possessed of a principle of vi- 

 tality, active and passive, sensible of the action of external 

 agents, and capable of organization. 



In animals of red blood it is invariably produced by the red 

 arterial capillaries. This I hold to be an undeniable fact. In the 

 most transparent and colourless parts, where no coloured vessels 

 are to be seen, the secretion of coagulable lymph is preceded by 

 an afflux of red blood, and this, after symptoms of inflammatory 

 action had entirely ceased, or where it has never existed, as in 

 the progress of the reproductions of the tails of tad-poles. It is, 



