DERIVED ORGANIZATION 109 



gniberi, one of the soil amebae. She describes the nucleus of this 

 organism as containing a typical endosome within which an endobasal 

 body is embedded. At the period of flagellation this endobasal body 

 divides and one daughter element migrates through the substance of 

 the endosome and through the nucleus to the cytoplasm, retaining its 

 connection throughout with the intranuclear kinetic element (Fig. 

 59, C). In the cytoplasm it becomes a basal body which gives 

 rise to the kinetic elements of the flagella. In these cases the ex- 

 truded kinetic element combines the functional characteristics of a 

 blepharoplast and a basal body or group of basal bodies. In this 

 dual capacity it may be regarded as a blepharoplast— basal body. 

 In Dimasiigamoeba bistadialis according to Puschkarew it divides, 

 one part remaining as a blepharoplast, the other becoming a basal 

 body; the two parts, however, are connected by a rhizoplast and 

 rhizoplasts connect the blepharoplast with the endobasal body (Fig. 

 59, B). 



In Bodo lacertae according" to Belaf the centrioles after division 

 are taken into the daughter nuclei. Here the kinetic elements, 

 although originating from an endobasal bod} 7 , are different in func- 

 tion from those described in the preceding paragraph. Forming 

 the poles of the mitotic spindle they are correctly described as 

 centrioles, but apparently they again become endobasal bodies 

 (Figs. 33, 34, p. 65). 



While the flagella appear to emerge directly from the nucleus in 

 some cases, e. g., in Mastigamoeba invertens according to Prowazek, 

 or Codosiga botryiis according to Doflein, in many cases they take 

 their origin actually from kinetic elements in the form of centrioles 

 which lie on the outside of the nuclear membranes, as in Mastigina 

 setosa, Phialonema cyclostoma, Cercomonas longicauda, Oicomonas 

 termo, or Chilomastix gallinarum (Fig. 60). In such cases, illustrated 

 by Chilomastix aulostomi according to Belaf (1921), centrioles, 

 become the basal bodies, and the latter become centrioles. In 

 such cases the basal bodies are unquestionably blepharoplasts. 



In other cases the blepharoplast does not remain connected with 

 the nucleus by any fibrillar process, but as an entirely separated 

 and independent kinetic element gives rise to the flagella at or near 

 the anterior end of the cell (Leptomonas jaculum) or Herpetomonas 

 gerridis (Fig. 169, p. 366). In Chilomastix mesnili Kofoid and Swezy 

 (1920) describe three blepharoplasts, one of which gives rise to two 

 flagella, another gives rise to one flagellum and the parastyle, the third 

 to the parabasal, peristomial fibril and the cytostomal flagellum 

 (Fig. 60, B). Boeck (1921) has confirmed these findings. Or, the 

 blepharoplast may migrate toward the posterior end of the cell 

 where with or without division to form blepharoplast and basal body 

 it gives rise to a flagellum, which becomes the vibratile margin of 

 an undulating membrane as in the majority of trypanosomes (Fig. 



