This discussion anent the fundamental chemical uniqueness of each species of ameba is of course not complete without an examination of the views expressed to the contrary. And it is to this side of the discussion that we may now briefly direct our attention. CHAPTER VI THE SPECIES QUESTION After the discovery of the ameba by Rösel v. Rosenhof and the introduction of the Linnean system of nomenclature, the number of new species of amebas that were reported increased rapidly. But in 1856 Carter suggested that what had been described as _A. radiosa_ probably was a young stage of _A. proteus_. With the general acceptance of the Darwinian Natural Selection Hypothesis, the ameba came to be looked upon as standing at the bottom of the scale of organisms, and consequently was supposed to lack generally such characters as the higher forms possessed. The ameba became the representative of the “primordial slime” from which by slow stages the other organisms were evolved. So of the sixty odd species which had been described up to Leidy’s (’79) time, Leidy, following the suggestion of Carter, was inclined to think that the great majority of these represented only changes of shape of about four species (not including the several species that were then known to be parasitic). Since Leidy’s time the prevailing tendency has been to regard most of the “new” species as mere environmental or life cycle stages of a very few species. A very noted exception to this tendency, however, has been Penard’s (’02) great work on the amebas and other rhizopods of the Leman Basin, in which he describes forty-five species of amebas (including _Gloidium_, _Protamoeba_, _Amoeba_, _Dinamoeba_, _Pelomyxa_), paying attention mainly to the readily observed ectoplasmic and endoplasmic characters, and the appearance of the resting nucleus.