1020 



PARASITES OF PROTOZOA 



investment of short spirochetes, that pockets may be formed inward from 

 the surface, enclosing some spirochetes. This was noted by Kirby (1936) 

 in Pseudodevescovma tmiflagellata, and by Grasse (1938) in Caduceia 

 theobromae and P. punctata. Grasse noted further that the pockets in 

 the former species may become closed, so that spirochetes are enclosed 



Figure 212. A, spirochetes adherent to Trichodinopsis paradoxa; B, microorganisms 

 on the capitulum of the axostyle of Macrotrichomonas pulclora from Glyptotermes dubius ; 

 C, adherent spirochetes on Pscudodevescovina uniflagellata, with enlargement in ecto- 

 plasm at point of adherence of each ; D, E, rods adherent to Macrotricloomonas sp. from 

 Procryptotermes sp., showing the cup-shaped structure in the ectoplasm at the end of 

 each rod. (A, after Cepede and Willem, 1912; B-E, original.) 



in vacuoles in the cytoplasm. He believed also that the external, fusiform 

 bacilli may at times enter the cytoplasm and be digested; but this opinion 

 may have been based on the presence of an intracytoplasmic symbiont, 

 which actually is quite different, as was noted in Caduceia nova and C. 

 theobromae by the writer (1936, 1938a). 



The possible physiological relationship between the adherent spiro- 

 chetes and their flagellate hosts has been considered by Cleveland ( 1928) 

 and Grasse (1938). Cleveland thought at first that they might live in 

 some sort of mutualistic relationship; but he found that when the spiro- 



