Quinanil as a Bactericidal Agent in the Isolation of an Insect Flagellate

Abstract

A flagellate from Polietes lardaria, closely allied to Herpetomonas muscarum, has been repeatedly isolated in bacteria-free culture by the use of quinanil after numerous attempts to isolate it by other methods with one exception had failed. The flagellates were exposed to 1/10,000 or 1/100,000 quinanil for 2–4 or more hours and cultivated in Locke serum agar, the medium for the first subculture containing quinanil in concentrations of 1/10,000 or 1/50,000. The proofs of the purity of the cultures were exhaustive.We are greatly indebted to Dr St John-Brooks and the National Collection of Type Cultures for certain of the flagellates isolated by Noguchi and Tilden. One of us (F. C. H.) has also been in receipt of grants from the Medical Research Council, and he would like to take this opportunity of expressing his thanks to that body.