OF THE ALIMENTARY TRACT 113 



them. When erythrocytes are ingested they are 

 rapidly destroyed, thus apparently accounting for 

 the fact that they are rarely recognized in the 

 amoebae. 



Ohira and Noguchi (1917) probably first cultivated 

 Endainoeha gingivalis, in a medium of ascitic fluid 

 and Ringer's solution in equal parts. If so, this was 

 the first successful cultivation of a parasitic amoeba. 

 It has been extensively cultivated by Drbohlav 

 (1925), by Howitt (1925), and by Dobell (1926), a 

 favorable medium for its growth being the L. E. A. 

 preparation of Boeck and Drbohlav (1924) as modi- 

 fied by Drbohlav, described in the cultivation of Eiid- 

 amoeba histolytica. Howitt recommends the use of 

 0.25 grams of glucose instead of 2.5 grams, as origi- 

 nally given, in making up Locke's solution. 



In culture Howitt (1926) found that emetine in 

 dilution of 1 to 25,000 diminished but did not elim- 

 inate the amoebae and a few were alive in dilution of 

 1 to 1660. Stovarsol was the most effective amoebi- 

 cidal agent used. 



Koch (1926) found acriflavine in dilution of 1 to 

 200,000, acridine yellow R 1 to 90,000, and aurimine, 

 diluted 1 to 60,000, lethal to the amoebae. These 

 dyes were not injurious to the gums of rabbits and 

 it was suggested that they might be used in the hu- 

 man mouth. Koch (1927) also found the amoeba to 

 be resistant to lower temperatures than that of the 

 body, while it could be killed by a temperature of 

 55 °C. in two minutes, by 52 °C. in ten minutes, and 



