G2 



BIOLOGY OF THE PROTOZOA 



m o. 



e n d. 



elongation continues until a thin fibril, called a centrodesmose, 

 alone connects the two halves. The centrodesmose ultimately 



breaks and its substance is ab- 

 sorbed by the two daughter ele- 

 ments. [See also Baker, and Hall 

 (1923).] In the rhizopod Chlamy- 

 drophrys stercorea, as well as in 

 the flagellate Bodo ovatiis, the 

 endobasal body which is quite 

 similar to that of Euglena, divides 

 subsequently to division of the 

 chromatin (Schaudinn, Belaf, 

 Fig. 29), while in Amoeba crystal- 

 ligera (Schaudinn) there is no 

 centrodesmose formed during 

 division, a condition nof un- 

 common in the rhizopods (e. g., 

 Arcella vulgaris according to 

 Swarczewsky ; Vahlkampfia Umax 

 [Fig. 28], and many species of 

 Endameba). Not only is this 

 simple type of endobasal body 

 found in rhizopods and flagel- 

 lates, but also in some cases in 

 the more complex ciliates, where, 

 in Chilodon cucullus, for example, the macronucleus contains a definite 

 endosome which behaves exactly like that of Euglena. It is highly 



Fig. 30. — Chilodon sp. Macronucleus 

 with endosome and endobasal body (end) . 

 (mo) Mouth surrounded by pharyngeal 

 basket. (Original.) 



B 



Fig. 31. — Endamoeba dysenteriae (Councilman and Lafleur). Two stages in the 

 metamorphosis of endosome and endobasal body. (After Hartmann.) 



probable that in all of these cases the endobasal body is em- 

 bedded in a core of plastin. 



