The Parasitic Amoebae of Man

es and to the difficulty and labor of studying their life cycle. While for years all authorities have agreed that these organisms belong to the Protozoa, almost every writer, until recently, has differed in his classification or in his conception of the biological history of the amoebae associated with dysentery, and it was not until Schaudinn's observations were published that a really satisfactory classification of these parasites was possible. However, it is probable that the present accepted classification may be found more or less erroneous as our knowledge increases, and it should be understood that in any of the amoebce in which the life cycle has not been thoroughly worked out, classification can only be provisional. There are a few well- studied species occurring in man in which the presentclassification may be said to be final, but other species have been described and classified which are still in doubt and in which the present classification may or may not be correct. The Amoebina are divided by zoologists into the Reticulosa, having filamentous pseudopodia; and the Lobosa, having lobose pseudopodia; the latter are divided into the Gymnamoeba, in which the protoplasm is naked; and the Testacea, in which the protoplasm is surrounded by a shell. The parasitic amoebae of man belong to the Gynmamoeba, or naked amcebae having lobose pseudopodia, and are placed in the genus Entamoeba created by Casagrandi and Barbagallo. All free-living forms are pl...