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



the highly characteristic multinucleate cells, may again assume the mitotic 

 method of increase, and vice versd. A curious feature in the further division 

 of these multinucleate cells, or syncytia as they may, perhaps, he more 

 appropriately termed, is seen in the almost invariable circumstance that, 

 on the resumption of mitotic activity, all the nuclei are in exactly the same 

 phase. 



This simultaneous character of the process is one which is shared by 

 many other syncytia, e.g., the myxomycetes. In these organisms, the nuclei 

 are commonly observed not only to be dividing simultaneously over a 

 considerable area of the plasmodium, but they also exhibit identical phases 

 of the process at any given time. In examples of this simultaneous mitosis 

 within the neoplastic syncytia, it often happens that the spindles of some, or 

 even all of the dividing nuclei, become more or less intimately fused 

 together, and in this way various forms of pluripolar mitosis are produced. 

 Probably these pluripolar divisions owe their origin chiefly to the cause just 

 indicated. 



The figures produced are extremely variable, and it not unfrequently 

 happens that, whilst the chromosomes belonging to the different nuclei 

 are aggregated in the centre, the poles of three or more of the spindles 

 involved are quite separate. In other examples the groups of chromosomes 

 do not coalesce, but each equatorial plate is quite distinct, and lies in a plane 

 different from that occupied by the equatorial plates of the other spindles. 

 But when a more intimate fusion of the ends of two or more spindles takes 

 place, it is obvious that the daughter nucleus formed in relation to such 

 unions will receive an excessive number of chromosomes. 



We would call special attention to the fact that giant cells of this 

 character, also containing several nuclei, are present not only in the normal 

 human testis, but also in the so-called red bone marrow, and that pluripolar 

 mitosis may occur in such cells in a manner precisely similar to that so 

 characteristic of cancerous tissue. The divisions of these early cancerous 

 cells also exhibit other characters likewise encountered in the cells of the 

 testis. Very often the daughter chromosomes do not move regularly towards 

 the poles, but some either stray out of the direct line, or in other ways 

 occupy unusual positions. These figures are also well known to occur in the 

 heterotype division of some spore mother-cells of plants. In yet other 

 examples of divisions in cancerous tissues, we have confirmed the observation 

 of Von Hansemann that some of the chromosomes, as they are passing to the 

 spindle poles, get ahead of their fellows, and form isolated or grouped 

 chromatic particles that look as if they are about to be left out in the 

 cytoplasm when the daughter nuclei become reconstituted. These figures 



