Studies of Endamoeba blattae (Bütschli)

A detailed study of the life history and cytology of Endamoeba blattae (Bütschli, 1878) has confirmed many of the findings of earlier workers and added to the knowledge of the processes of mitosis, excystation, metacystic and later development of this animal. Metacystic transformation has been seen to give rise to a form indistinguishable from E. thomsoni Lucas ('27). The number of chromosomes found in dividing stages of this trophozoite appears to be half that found in the large adults and indicates the possibility of a gametogenic type of reproduction differing from that described by Mercier ('10). Upon the basis of these findings and of a reclassification of the nuclear types found among the larger endozoic amoebae, it is proposed to erect, within the genus Endamoeba Leidy (1879), three sub‐genera to serve until further knowledge permits a more permanent arrangement, as follows: Genus Endamoeba Leidy (1879). Type—E. blattae (Bütschli, 1878). Sub‐genus Endamoeba. Type—E. (E.) blattae (Bütschli, 1878). Sub‐genus Placoidia. Type—E. (P.) minchini Mackinnon ('14). Sub‐genus Poneramoeba. Type—E. (P.) histolytica Schaudinn ('03).