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



second or third cell from inside the margin the altered character is easily 

 recognised (fig. 1, b). The cells exhibit an increase in cytoplasm, a comparative 

 absence of secretory activity, and a peculiar and well-defined change in the 

 appearance of the nucleolus. The alteration in this last-named structure 

 consists in its larger size and denser appearance. Furthermore, very many 

 nuclei are to be seen in a state of active division. Whilst some exhibit 

 various stages of mitosis, others are clearly undergoing fragmentation or 

 amitosis. 



At this stage of the development of the tumour, the peripheral cells that 

 are dividing mitotically show all the characters of ordinary premaiotic 

 divisions, and the normal number (32) of chromosomes can frequently be 

 counted with certainty (tigs. 5 and 10). But concomitantly with the first 

 changes indicated in the epithelial cells at the edge of the neoplasm, a marked 

 activity may be observed to take place on the part of the leucocytes. These 

 bodies are seen to be in a condition of active migration and multiplication, 

 much like that which occurs during the early stages of simple inflammation. 

 In the subsequent stages, however, the early parallelism with inflammatory 

 processes is lost, and there supervenes a remarkable phase in the further 

 development of the cancerous cells. Not only do the cells of the tissue in 

 question multiply with great rapidity, whilst the leucocytes amongst them 

 are enormously increased in number, but the latter are seen not infrequently 

 to force their way into the cancer cells, particularly in the so-called " giant 

 cells," where, however, they are still to be recognised with ease and certainty 

 (figs. l,x, d, 11, 12, 13). This circumstance has already been noticed by others, 

 but we have been led to attach a somewhat special importance to its occurrence. 

 Some writers have suggested that the cancer cells are acting phagocytically 

 upon the leucocytes, but, as a matter of fact, the further sequence of events 

 indicates that the cancer cells are no more to be regarded as attacking the 

 leucocytes than the latter as destroying the cancer cells. There can be no 

 possible doubt that the leucocytes actively force their way into the elements 

 in question. They may not seldom be observed to be in close juxtaposition 

 with these, or in a hollowed depression, or finally they may be discovered just 

 within the cell membrane, where they are easily recognised on account of 

 their characteristic nuclei (fig. 11). They show no sign of disintegration — at 

 least, in the great majority of cases — and the fact that they may persist for a 

 considerable time without destroying the cell into which they have invaded, 

 is proved by examples in which a leucocyte lying in the cancer cell is seen to 

 be surrounded by several nuclei that have clearly originated by the frag- 

 mentation of the original cell nucleus, and, indeed, one of these is shown to 

 be still dividing amitotically. 



