50 REVIEW — TEOPICAL MEDICINE, ETC. 



Dysentery — Pseudopodia 



continued Large and easily distinguished. Hard to distinguish. 



Certain ectoplasm and entoplasm. Entirely ectoplasm. 



Vacuoles 

 Many. Often absent. 



Never more than one. 



Nucleus 



Often absent. When present its structure Almost invariable, with well-defined 



hidden except in stained specimens. Nuclear nuclear membrane and other 



membrane not well defined. Changes posi- structure. 



tion markedly. In moving, organism retains relative 



position. 



Bed Corpuscles ingested 

 Many. None observed. 



Motility 



Great progressive motility. Often absent, or, when present, of 



limited extent and short duration. 



Losch, quoted by Manson, gives very similar characteristics, and in addition mentions — 



Multiplication 



In the intestine by fission and budding. On In the intestine by binary fission 



hard fseces or outside the body resistant and also by multiple fission into 



spores formed without encystment. 8 amcebulae. On hard fseces and 



outside the body encystment and 

 formation of 8 amoebuke. 

 (These develop when swallowed). (These are set free when swallowed). 



Musgrave and Clegg,^ in a long paper on the cultivation and pathogenesis of amoebae, 

 oppose Schaudinn's views, and believe that the name Amoeba coli (Losch) should still be 

 retained to represent those amcebae which are found in human intestines. They do not 

 believe in differentiating between E. coli and E. histolytica for the following reasons : — 



Amoebae found in the stools of so-called healthy people do not always conform to the requirements for 

 E. histolytica. Cultures of amcebae answering more nearly the description given for E. coli, can Ijy methods 

 described in this paper (M. & C.) be made to produce ulcerative colitis in man and monkeys and abscesses of the 

 liver, omentum, spleen and lungs in monkeys. In cultures, single species of amoebae are often found 

 which are characterised by possessing a combination of some of the features which have been described 

 as distinctive for different species. Amcebae from many extraneous sources, and presumably saprophytic, may be 

 cultivated on artificial media, and with such cultures ulcerative amoebic colitis may be produced in man and 

 animals, and abscesses brought about in the liver, lung, omentum, spleen and muscular tissues of animals. 



These conclusions are, however, challenged by Vedder,^ who points out that many of 

 them are based on fallacies and faulty working methods, and concludes that the criticisms 

 are not well founded. 



Ashburn and Craig^* have worked at the presence of amcebae in healthy persons, 

 American soldiers in the Philippines. They examined 100 cases. In 72, E. coli 

 was present ; in 2, E. dysenteriie. None of the 72 had dysentery or diarrhoea at the time of 

 examination, nor had they ever been on the sick list owing to these diseases. The two men 

 with E. dyseyiteriie appeared well, but were found to have dysenteric symptoms and were 

 eventually invalided for chronic amoebic dysentery. Their interesting conclusions are as 

 follows : — 



In the Philippine Islands a very large proportion of white men are infected with E. coli, and such 

 infection does not result in symptoms of diarrhoea or dysentery ; in many of the cases the amoebse disappear 

 but in the large proportion E. coli may be fouml even after the lapse of nine mouths, during which time 

 the infected individuals have remained in perfect health as regards dysentery or diarrhoea. 



We also conclude that E. coli differs very markedly from E. dysenteria; as regards morphology, and that it is 

 possible to distinguish these two species of amoebae by their morphological characteristics as observed in fresh 

 specimens of faeces. We do not believe that the very large proportions of infections with E. coli which we have 



' Musgrave, W. E., and Clegg, M. T. (November, 1906), "The Cultivation and Pathogenesis of Amoebae." 

 Philippine Journal of Science, p. 909, Vol. I. 



- Vedder, E. B. (June Ist, 1907), " Is the Distinction between Entamoeba Coli and Entamoeba Dysenteriae 

 Valid?" Journal of Tropical Medicine and Hygiene, p. 190. 



' Ashbnrn, P. M., and Craig, C. F. (September, 1907). The Military Surgeon, p. 222, quoted in Indian 

 Medical Oasette, December, 1907. 



• Article not consulted in the original. 



