302 SOME MINUTE ANIMAL PARASITES 



parasitized. Spirochaetes and Amoebae are found 

 in hollow teeth ; Entamoebae invade the intestine. 

 Trichomonas and Lamblia among the flagellates, and 

 Balantidium and Nyctotherus representing the ciliates, 

 as well as Amoebae, are associated with diarrhoea and 

 dysentery. The blood can harbour several species 

 of malarial parasites, spirochaetes, and trypanosomes, 

 the latter also finding their way into the nervous 

 system. The tissues may be infected by Entamoebae 

 in liver abscess, Sarcosporidia in the muscles, Coc- 

 cidia in the bowel, and stages of parasites, such as 

 Trypanosoma cruzi, found lodged in the tissue of the 

 lungs, as well as in other situations. Nor does this 

 exhaust the list, for nasal and aural tumours can be 

 produced by protozoal agency. It is suspected that 

 many complaints, such as smallpox, trachoma, 

 hydrophobia and measles, the causal agents of which 

 are little understood, are due to the agency of Pro- 

 tozoa as yet incompletely determined. 



The importance of the study of the Protozoa 

 in relation to man's health is undoubted. The 

 enormous losses of life in the various attempts to 

 cut the Panama Canal are witnesses of the malignant 

 power of various Protozoa. The sacrifice of many 

 lives in developing the resources of Africa is evidence 

 of their effect. The retarded development of parts 

 of South America, India, and China is the result, 

 not of lack of attempts, but of the presence of 

 protozoal diseases, that are dispersed actively by the 

 agency of various insects and ticks. 



The aims of medicine may be summed up as 

 making the human frame healthier, and rendering 



