684 SCIENCE PROGRESS 



cells consists in the comparison between the records of the 

 numbers of chromosomes found in individual cells of cancer, 

 reproductive tissue and inflammatory tissue respectively. The 

 numbers of cells dealt with are so large as to render the influence 

 of small personal errors or of chance of no practical importance. 



The accompanying figures ! show graphically how the pro- 

 cesses of reduction in the number of chromosomes in the cells 

 of (i) human reproductive tissue, (2) a rapidly growing but 

 unulcerated (uninflamed) cancer, (3) a cancer with a considerable 

 amount of inflammation superimposed on the meiotic phenomena 

 and (4) ordinary inflammatory tissue, compare with each other. 

 A graph including 800 cells from inflamed and uninflamed 

 malignant growths confirms the points illustrated here (5). 



Other evidence shows that the peculiar forms of chromo- 

 somes found usually only in gametogenic cells appear also in the 

 cells of malignant growths but not in those of inflammatory tissue. 2 



Against this evidence are only generalised statements that 

 the numbers of chromosomes in the cells of malignant growths 

 do not appear to be exactly half the somatic number and this in 

 spite of the fact that over five years have elapsed since the first 

 set of figures were published. 3 No systematic counts supporting 

 the contradictions have been published and nothing that tends to 

 do more than emphasise the point that inflammatory are often 

 superimposed upon the meiotic phenomena. The evidence 

 against the occurrence of specialised forms of chromosomes is 

 equally unsatisfactory. 



The only cells in the body of any multicellular organism, 

 whether plant or animal, in which the symmetrical reduction 

 in the chromosomes to half the somatic number takes place as a 

 physiological (normal) process, are the gametogenic cells and 

 these gametogenic cells are the only cells that normally pass 

 out of somatic co-ordination. Therefore, apart from any other 

 and perhaps equally important though less easily demonstrated 

 points of resemblance, the suggestion is very strong indeed that 

 the meiotic phenomena are due to the cells having passed out 

 of somatic co-ordination. The gametogenic cells 4 differ but little 



1 From Walker and Wittingham, op. cit. 



2 Walker and Whittingham, op. cit. 



3 Farmer, Moore and Walker, Proc. Roy. Soc. B, vol. lxxvii. 1906. 



4 The cells whose descendants are destined to produce gametes. This term 

 obviously excludes the mature gametes. 



