_Natural hosts._--_Blatta orientalis_, _Blattella germanica_, _Periplaneta americana_, U.S.A. (Young, 1935): The organism when present occurs in large numbers in the posterior part of the intestine near the anus. The protozoan was successfully cultivated in a hemoglobin-saline medium. Family OXYMONADIDAE =Oxymonas doroaxostylus= (Cleveland et al.) _Synonymy._--_Saccinobaculus doroaxostylus_ Cleveland et al. [Cleveland, 1950]. _Natural host._--_Cryptocercus punctulatus_, U.S.A., Appalachian and Pacific coast areas (Cleveland et al., 1934). =Oxymonas nana= Cleveland _Synonymy._--_Saccinobaculus minor_ Cleveland et al. [Cleveland, 1950]. _Natural host._--_Cryptocercus punctulatus_, U.S.A., Appalachian and Pacific coast areas (Cleveland et al., 1934). Family DINENYMPHIDAE =Saccinobaculus ambloaxostylus= Cleveland et al. _Natural host._--_Cryptocercus punctulatus_, U.S.A., Appalachian and Pacific coast areas (Cleveland et al., 1934). =Saccinobaculus lata= Cleveland _Natural host._--_Cryptocercus punctulatus_, U.S.A. (Cleveland, 1950b): There are at least two other species of _Saccinobaculus_ in _C. punctulatus_ that have not been described. =Notila proteus= Cleveland _Natural host._--_Cryptocercus punctulatus_, U.S.A., Appalachian and Pacific coast areas (Cleveland, 1950b). Family TRICHOMONADIDAE * =Trichomonas hominis= (Davaine) _Experimental vectors._--_Blatta orientalis_, South Africa (Porter, 1918); Italy (Mariani and Besta, 1936). _Periplaneta americana_, South Africa (Porter, 1918); U.S.A. (Hegner, 1928). =Trichomonas= sp. _Natural vector._--Cockroach, Venezuela (Tejera, 1926): Organism found in digestive tract of the cockroach. Family HEXAMITIDAE =Hexamita cryptocerci= Cleveland et al. _Natural hosts._--_Cryptocercus punctulatus_, U.S.A. (Cleveland et al., 1934). _Panesthia angustipennis_, Philippine Islands (Kidder, 1937). =Hexamita periplanetae= (Bĕlăr) _Synonymy._--_Octomitus periplanetae_ Bĕlăr [Kudo, 1954]. _Natural hosts._--_Blatta orientalis_, U.S.S.R. (Zasukhin, 1930): Organism is found in the hind gut. Eighty-five percent of over 3,000 _B. orientalis_ contained this organism. _Periplaneta americana_, Philippine Islands (Hegner and Chu, 1930). "Küchenschaben," Austria (Bĕlăr, 1916). =Hexamita= sp.? _Natural host._--_Leucophaea maderae_, Philippine Islands (Hegner and Chu, 1930): The flagellates were present in large numbers. * =Giardia intestinalis= (Lambl) _Experimental vectors._--_Blatta orientalis_, South Africa (Porter, 1918). _Blattella germanica_, Brazil (Pessôa and Corrêa, 1927). _Eurycotis floridana_, U.S.A. (Young, 1937). _Leucophaea maderae_, Brazil (Pessôa and Corrêa, 1927). _Periplaneta americana_, South Africa (Porter, 1918); Gold Coast Colony (Macfie, 1922); Brazil (Pessôa and Corrêa, 1927); U.S.A. (Young, 1937). _Periplaneta brunnea_, U.S.A. (Young, 1937). Cockroaches, Venezuela (Tejera, 1926); Argentina (Bacigalupo, in Tejera, 1926). * =Giardia= sp.