In addition, there are two or three obervations to hand which shew that piscine, amphibian and mammalian Trypanosomes may also become attached.
The " carrier " of a Trypanosome of warmblooded vertebrates is, in all instances so far described, an insect, generally a member of the Diptera; in the case of parasites of cold-blooded vertebrates the same role is usually played by an ichthyobdellid leech (piscine forms), but possibly, now and again, by an Ixodes (amphibian or reptilian forms).