532 



APPENDIX D. 



a necrosis with softening and partial liquefaction, attended by little or 

 no suppurative change. The amoebae have also been found in the sputum 

 when a liver abscess has ruptured into the lung, as not very infrequently 

 happens. 



Relations to the Disease. It may be stated in the first place that 

 satisfactory cultures of these amoebae outside the body have not been 

 obtained. Kartulis announced that he had cultivated the organism on 



straw infusion, but it is now recog- 

 nised that his results are erroneous, 

 the amoebae observed by him being 

 probably derived from the infusion 

 itself. In fact, everything seems to 

 show that the amoebae in their usual 

 form rapidly disintegrate outside 

 the body, and it is still unknown in 

 what form they survive and lead 

 to the propagation of the disease. 

 The points of distinction between 

 the amoeba of dysentery and the 

 ordinary amoeba coli, so far as the 

 FIG 170. -Section of wall of liver ab- morphology is concerned, are that 



the latter is on the whole of smaller 



scess, showing an amoeba of spherical form 



with vacuolated protoplasm. From a case 



published by Surgeon-major D.G. Marshall. gize itg pro toplasm IS more finely 



X 1000. 



granular, and it does not appear to 



take up red corpuscles, etc., as is the case with the former. The dis- 

 tinction, however, can only be definitely drawn by means of experiment. 

 Injections of certain quantities of dysenteric stools containing the amoebae 

 into various animals per rectum have been carried out by different ob- 

 servers, especially by Kruse and Pasquale. In cats, in the majority of 

 cases, a haemorrhagic enteritis is produced, amoebae being present in 

 the stools and also invading the mucous membrane of the intestine in the 

 ulcerated areas which are sometimes formed. The deep infiltration of 

 the submucous coat by the amoebae, which is so characteristic a feature 

 in the human disease, does not occur in these animals. Not infrequently 

 death follows. Kruse and Pasquale obtained corresponding results when 

 the material from a liver abscess, containing amoebae without any other 

 organisms, was injected. In the absence of cultures of amoebae outside 

 the body, this result must be taken as strong evidence that the disease 

 produced in cats is really caused by the amoebae. Similar injections 

 with material containing amoebae derived from other sources are unat- 

 tended by any pathogenic effects of similar nature. , Feeding the ani- 

 mals with material containing the amoebae is much more uncertain in its 

 effect. Quincke and Roos obtained no effects when the amoebae were 



