FAT. 227 



The second set of observations relate to the nucleus. 



If a thin slice of the fat of the pig be pressed as before 

 between two slips of glass with a moderate degree of pres- 

 sure, and then be submitted to the microscope, in very many 

 of the cells will be seen a dark nucleus-like body. This 

 experiment will not, however, always succeed. (See Plate 

 XIX. fig. 1.) 



A body of a similar description, but of a more defined 

 form, is very frequently encountered in the decomposing 

 cells of marrow fat ; this nucleated condition of the cells 

 preceding their rupture. (See Plate XIX. fig. 3.) 



Again, in some fat cells contained in a small encysted 

 tumour removed from over the nasal bones, and kindly sent 

 to me for examination by W. H. Ransom, Esq., of Univer- 

 sity College Hospital, (to whose zeal and intelligence I am 

 indebted for many interesting specimens of morbid structure,) 

 nucleoid bodies were distinctly visible even without pres- 

 sure, although they became more apparent after a gentle 

 degree of compression had been applied. (See Plate XIX. 

 fig. 6.) The apparent nuclei in the cases related differed from 

 each other somewhat, being more defined and darker in the 

 two latter than in the former ; the cells themselves too were 

 not identical in appearance ; thus the margins of those of the 

 pig and of the human marrow fat were smooth and distinctly 

 defined, while those from the tumour were less regular and 

 distinct. (See Plate XIX. figs. 1. 3. 6.) 



Now these nucleus-like bodies in the several cases men- 

 tioned, although occupying the position of nuclei and pre- 

 senting the appearance of such, it is very possible were not 

 in reality true nuclei ; it seems to me that their formation 

 might be accounted for without any reference to a nucleus. 

 Thus with respect to the nucleoid bodies in the cells of the 

 pig produced by pressure, their formation might be ex- 

 plained as follows : the mutual compression of the fat vesi- 

 cles upon each other would tend to occasion a condensation 

 of the semi-fluid contents in the centre of each, and in this 

 way the appearance of nuclei would be produced. 



Again, the semblance of a nucleus in the decomposing 



