CRAIGIASIS 139 



later escape from the cyst and develop into little flagellated or- 

 ganisms called " swarmers " (Fig. 40A and B). These grow to 

 several times their original size (Fig. 40C), multiply a few times 

 by simple division (Fig. 40D), and finally lose their flagellum and 

 pass again into the ameboid stage. C. migrans (Fig. 40G to L), 

 as described by Barlow in Honduras, where C. hominis also exists, 

 differs in that each flagellate on attaining full development passes 

 directly into the ameboid form without first multiplying. The 

 swarmers (Fig. 40H) are larger and fewer in number than are 

 those of C. hominis, and the adults (Fig. 40K) average a slightly 

 larger size. 



The Disease. — Barlow describes craigiasis as he found it in 

 Honduras as more insidious in its development than amebic 

 dysentery and not so distressing in its early stages, but ulti- 

 mately quite as dangerous a disease. The symptoms — diar- 

 rhea with bloody and mucous stools, loss of appetite, abdominal 

 pain, etc., — are quite similar to those of amebic dysentery. 

 In Barlow's experience liver abscess is even commoner in craigi- 

 asis than in amebic dysentery. The disease is looked upon as 

 more dangerous to the community than amebic dysentery because 

 of the larger per cent of healthy carriers, who, though showing no 

 marked symptoms for years, may be a constant means of spread- 

 ing the infection. The usual source of infection is believed to be 

 polluted water. 



Treatment. — Although emetin is as destructive to Craigia 

 as it is to other amebae, injections of the hydrochloride are not so 

 effective as in amebic dysentery since only the tissue-dwelling 

 ameboid forms are reached by the emetin in the blood, while 

 the free-swimming flagellated forms escape. Complete and 

 rapid cure is best effected by combined treatment with emetin 

 injected into the blood and ipecac taken by mouth, accompanied 

 by occasional flushing of the bowels with saUne laxatives or 

 enemas to remove the cysts. The same preventive measures 

 used against amebic dysentery are applicable to craigiasis. 



The Mouth Amebae 



The fact that our mouths are inhabited by amebae of several 

 species has been known for many years, but only recently has 

 much interest centered in them, this interest being due to the 



