THE CELL DOCTRINE. 67 



extremely monotonous structure, recurring- with ex- 

 traordinary frequency in living organisms."* 



More recently, however, Virchow is reported as 

 not regarding the " cell-wall " as an essential part of 

 the cell, as stated in Cellular Pathology ; but that a 

 nucleus surrounded by a molecular blastema was suffi- 

 cient to constitute a cell ; then he says that the outer 

 part of this cell blastema consolidates and forms a 

 cell-wall as Beale has shown, and that this takes 

 place in the amoeba when placed in water. f 



As thus defined, the cell is the seat of pathologi- 

 cal and phj'siological processes rather than the blood, 

 or the nerves. The cell is active — the ultimate mor- 

 phological element in which there is any manifesta- 

 tion of life, and beyond which the seat of real ac- 

 tion cannot be removed. Hence the term Cellular 

 Pathology rather than humoral, or neural, or soUd- 

 istic. The so-called exudations are not such in the 

 strict sense of the term, and the cells which they 

 contain, whether of pus or organizable lymph, are 

 the result of proliferation of previously existing cells. 

 Even " fibrin, wherever it occurs in the body exter- 

 nal to the blood, is not to be regarded as an excre- 

 tion from the blood, but as a local production," re- 

 sulting from the activity of the cells of the tissue 

 in which it is found, and conveyed to the surface by 

 the transudation of the serous fluids alone. :[: In the 



* Op. cit.,pp. 31, 34. 



■j- Letter from Berlin, in Edinburgh MedicalJournal, February, 

 1865. 

 J Virchow, op. cit., pp. 485-6. 



