350 Prof. Farmer, Messrs. Moore and Walker. [Nov. 17, 



1. That a primary growth originates in the first instance as the result of 

 a change in the nature of a number of previously functional somatic cells. 



2. That the transformation may affect a considerable number of cells, and 

 certainly continues to operate for some time. 



3. That, as the result of the change, mitotic and amitotic activity is 

 awakened, and proceeds rapidly, with a consequent increase in the mass of 

 affected tissue. 



4. That during this increase a remarkable activity prevails amongst the 

 leucocytes, at first resembling that seen in inflammatory processes, but finally 

 leading to the union of at any rate some of the affected cells with one or more 

 leucocytes. 



5. That in the subsequent divisions of these cells the nucleus of the 

 leucocyte divides simultaneously with that of the cancer cell, and their 

 chromosomes may become mingled in cleavage figure. 



6. That multinucleate cells (syncytia) may arise by mitosis or by amitosis, 

 unaccompanied with the division of the mass of protoplasm. 



7. That the resulting nuclei may divide normally and mitotically, or the 

 nuclear figures may be more or less mingled, and hence all sorts of variations 

 in the number of chromosomes may occur. But the mode of chromosome 

 evolution and division follows the somatic type. 



8. In addition, a form of mitosis occurs, leading to nuclei with half the 

 number of somatic chromosomes, and the phases closely accord with those 

 observed during the heterotype (first maiotic) mitosis of animals and plants. 



9. Subsequent divisions occur, in which the reduced number of chromo- 

 somes is retained, the type of division otherwise resembling that of ordinary 

 somatic cells. These mitoses fall into the category corresponding with the 

 post-maiotic mitoses of plants. 



10. During the maiotic and post-maiotic divisions in the cancerous cells, 

 structures are present which have been designated as Plimmer's bodies. 

 These are common to cancerous cells and to the reproductive cells of the 

 testis at a particular phase in their evolution. The only other cells in which 

 structures resembling the bodies in question have been observed are possibly 

 those forming certain of the leucocytes in bone-marrow. 



It will be evident from the above summary that the change from the 

 healthy to a cancerous development is intimately bound up with definite 

 change in the cells affected. The onset of the change is probably to be 

 attributed to the operation either of new stimuli upon the body cells, or to a 

 change in the constitution of the latter. Such an alteration might originate 

 in a variety of ways. For example, it might be ascribed to the influence of 

 a parasite. But we have never succeeded in tracing any such cause, and it 



