1018 PARASITES OF PROTOZOA 



The very long ones on the above-mentioned Stephanonympha had a 

 much larger number of turns, but none like those have been seen on 

 Devescovininae. 



Normally the spirochetes are in continual, very active flexuous move- 

 ment. They are not rigid, like Spirillaceae, although some observers 

 have compared them with spirilla. Their activity has been described by 

 Koidzumi (1921) on Holomastigotoides hartmanni, Light (1926) on 

 Metadevescovina debilis, Duboscq and Grasse (1927) on "Devescovina" 

 hilli, Kirby (1936) on Pseudodevescovina uniflagellata, and by others. 

 They can be studied best in living material by dark-field illumination. 

 Their movements are not synchronized, and are unco5rdinated either in 

 direction or activity. The difference between this movement and that 

 of cilia or flagella has impressed all students who have observed it. 

 As noted by Kirby (1936), they may move at an equally active rate 

 under the same environmental conditions, on moving flagellates, quiet 

 flagellates, dead flagellates, and detached balls of cytoplasm. This activ- 

 ity, together with their form, readily distinguishes them from flagella; 

 but distinction is less easy in iixed material, in which the form is often 

 less evident. 



The spirochetes do not, in the writer's experience, detach readily 

 in preparation of smears. Grasse (1938) stated that certain flagellates 

 lacking spirochetes may have lost them in consequence of fixation, but 

 offered no proof that this occurs. Spirochetes of P. uniflagellata were ob- 

 served to be rubbed off by movement of the large flagellate in close 

 contact with the cover glass, and severe manipulation might cause their 

 loss; but that treatment is more drastic than would ordinarily occur in 

 the preparation of specimens. 



The spirochetes can be removed, however, by relatively simple meth- 

 ods. Light found that treatment with iodine in 70-percent alcohol freed 

 the bodies of most Metadevescovina debilis of spirochetes. Cleveland 

 (1928) discovered that all the spirochetes could be removed, both from 

 the surface of the Protozoa and the lumen of the gut, by feeding the 

 termites on cellulose thoroughly moistened with 5 -percent acid fuch- 

 sin. That method was used by Sutherland (1933) to remove spirochetes 

 from Spirotrichony))iphella and Stephanonympha; and it has been used 

 in the study of many Devescovininae by the writer. Feeding Kalotermes 

 huhbardi for twelve days on filter paper moistened in 5-percent aqueous 



