Only one species of this genus is known, namely E. ambulans, Olliff. This extraordinary flea was obtained from a Porcupine Ant Eater (Tachyglossus aculeatus, Shaw = Echidna hystrix). Olliff in his paper " Description of a New Aphanipterous Insect from New South Wales," says that it "was found in large numbers on a Porcupine Ant Eater (Echidna hystrix) which was recently added to the collection of the Australian Museum." As a matter of fact I only know of three specimens, and these are in our cabinet. They are probably the only specimens in any collection. Our specimens are mounted on one slide and labelled "Echidnophaga ambulans, Olliff, on Echidna hystrix, N.S.W. TYPE."