PART II. CHARACTERS AND DIAGNOSIS 61 



membrane. The cells show all kinds of granular degenerative 

 changes, but very frequently one finds greenish homogeneous highly 

 refractile spheres in the cytoplasm of the cells. These spheres 

 are probably of a fatty nature, but their importance, from the 

 present point of view, is that they have been mistaken for nuclei 

 of amoebae or even red blood corpuscles. It is well to remember 

 that the nucleus of an amoeba is never a homogeneous refractile 

 body, but is recognized by the ring of granules at its periphery, 

 while the interior appears of much the same colour as the cyto- 

 plasm outside. While the cells which have been mentioned above 

 are the ones most commonly seen in the mucus of bacillary dysentery 

 there occur sometimes patches of mucus showing another type of 

 cell. These are elongated cells changed and distorted in various 

 ways and are evidently derived from the columnar cells of the gut 

 wall itself. This type of cell occurs very commonly in the mucus 

 one so often sees around the formed faeces of the post-dysenteric 

 condition. In these cases the cells seem to have originated from 

 mucous membrane of the lower part of the large intestine. The 

 pus and other cells described above are probably purely exudate 

 cells derived from the outpouring of liquid from lymphatics and 

 blood-vessels, while the latter are exfoliations from the gut wall. 

 The two plates are of outline drawings of cells made from a 

 bacillary dysentery stool and illustrate the cellular exudate on the 

 one hand and the exfoliation type of cell on the other (text figs. 1 

 and 2, pages 62 and 63). If films of this cellular exudate are stained 

 after wet fixation by iron haematoxylin all kinds of strange pictures 

 are developed, which are a result of the active phagocytosis and 

 nuclear degeneration which is taking place. The pus cells with 

 their fragmented nuclei when four portions are present may simulate 

 the cysts of E. histolytica. The remains of the nuclei of phagocyted 

 cells in the cytoplasm of larger cells may suggest reproductive 

 phases, such as schizogony of some protozoon, while it may be 

 impossible at times to distinguish between degenerating cells and 

 degenerating amoebae. With such a collection of curious and 

 unusual objects before one it is necessary to be on one's guard 

 against errors of interpretation. The characteristic features both 

 macro- and microscopic of the bacillary dysentery stool have been 

 insisted upon by observers before this. Bahr, in his account of 

 bacillary dysentery in Fiji, draws attention to the large cells which 

 may be mistaken for amoebae. Stitt in his " Manual of Tropical 

 Diseases " repeatedly refers to the characters of the bacillary 

 dysentery stool, the type of cell found in the cellular exudate, and 



