"FLAGELLATION" 175 



by L'Engle, of Philadelphia, who has also seen it occur 

 in poly nuclear leucocytes. When we examined fresh 

 blood-cells mixed with the pla,sma of cancer patients, 

 we again noticed that the lymphocytes extruded 

 granules in some cases apparently in response to 

 something in the cancer plasma, a point which Dr. 

 Macalister and I published in The British Medical 

 Journal on January 16, 1909. Dr. Buchanan, how- 

 ever, has informed us and this is a most interesting 

 point that he had previously seen similar extrusions 

 take place in cases of leukaemia, a fact which he 

 mentions in his book; and a fact which we shall 

 recall later on. We, however, had never seen these 

 extrusions occur unless alkaloid or cancer plasma had 

 been mixed w^ith the cells. 



As already mentioned, the commonly accepted 

 explanation regarding the cause of the reproduction of 

 cells by individual cell-division is not very satisfactory. 

 One of the characteristics of living matter is that it 

 is capable of reproducing itself, and the theory as 

 to its causation in animal cells was that they, being 

 living creatures, reproduce themselves because it is an 

 intrinsic function of the protoplasm that is to say, that 

 it is a vital propensity on the part of every cell to 

 divide automatically, so to speak, and to continue to 

 do so until it dies. This explanation, however, does 

 not harmonise with certain known facts concerning cell- 

 proliferation. For instance, physiologically cell-division 

 is influenced by conditions outside the cell. The limi- 

 tation of the size of an organ must be controlled by 

 some governing factor which influences not only the 



