QUESTIONS. 233 



the motile amoeba. A nucleus more or less central is also 

 easily made out. 



The Amoeba coll is stained easily by any of the nticleolar 

 stains, especially by methylene-blue. In its body may often 

 be seen foreign bodies, especially red blood-cells, but it rarely 

 contains leucocytes or fat. 



The motion of the amoeba is caused by the mechanism of 

 pseudopodia, which are blunt homogeneous processes, the pro- 

 trusion of a portion of the ectoplasm. Motion is sometimes 

 gradual and deliberate, at other times rapid, and is modified 

 by variations in temperature. 



Biology. Nothing is known as to the functions of nutri- 

 tion, respiration, and reproduction of the amoeba. It is found 

 occasionally in health in the secretions of the lower bowel, 

 and in cases of dysentery may disappear partially or com- 

 pletely from the stools during convalescence. They are also 

 frequently found in the pus of hepatic abscesses. 



Examination of the feces, especially the slimy portion of 

 dysenteric stools, and the pus in cases of suspected amoebic 

 infection, should be made in fresh specimens, when the live 

 amoebae may be easily recognized. Dried preparations are 

 made as for bacterial examination, and colored with aqueous 

 solution of methylene-blue. 



QUESTIONS. 

 Streptothrix. 



What is a streptothrix ? How does it resemble moulds? How does it dif- 

 fer from moulds? How does it resemble bacteria? 



Which are the best known of the streptothrices ? 



Why are the Bacillus tuberculosis and Bacillus diphtheria; believed to belong 

 to the class of the streptothrices ? 



What is the appearance of the lesion caused by streptothrices? 



Describe the Streptothrix adinomyces,nr ray fungus. How is it best stained? 



Give Mallory's staining method. 



Give the principal biologic characters of the Streptothrix actinomyces, 

 How does it grow on blood-serum and agar ? On gelatin ? On potato ? In 

 bouillon? 



What animals are susceptible to streptothrix infection ? Is the disease 

 transmissible from animal to animal or from animal to man? How are ani- 

 mals infected ? 



Describe the lesions produced by streptothrix infection. What causes the 

 suppuration? 



