BODO 171 



flagellum is inactive, and often is wound round the body 

 in a loose coil. 



There are several species of Bodo, of which Bodo saltans 

 alone exhibits the peculiarity of attaching itself by its ventral 

 flagellum and executing springing movements. The signific- 

 ance of this habit is doubtful, but it is supposed, that it is 

 during its anchored state, that it ingests solid food. Living as 

 it does in organic infusions impregnated with proteids and 

 other nutrient substances, it is more than probable that the 

 nutrition of Bodo saltans is largely a process of simple diffusion 

 through the whole surface of the body — that is, a saprophytic 

 mode of nutrition. But whether this be the case or not, it is 

 certain that the animalcule ingests solid food, for bacteria and 

 similar foreign particles can be seen in its protoplasm in various 

 stages of disintegration. As has been said, it is probable that 

 this solid food is ingested during the anchored state, though 

 the process has never been actually seen because of the cease- 

 less rapid movements of the creature. But many of the other 

 species have been seen to feed in true animal fashion. One 

 of the most interesting cases is Bodo angustatus, an organism 

 found in the cells of decaying potatoes. Normally it has two 

 flagella and the structure of a typical flagellate. But it 

 frequently passes into an amceboid condition and emits a 

 number of long and very fine pseudopodia : it is uncertain 

 whether the flagella are always withdrawn in this state or not. 

 In the amoeboid form Bodo angustatus attacks the starch 

 granules of the potato. Gradually spreading its body over a . 

 granule as large as or larger than itself, it completely envelops 

 it, and is often reduced to so thin a film of protoplasm as to 

 be hardly visible. Sometimes a flagellate form may be seen 

 to engulph a starch granule in the same way, without previously 

 passing into an amoeboid condition. In Bodo caudatus there 

 is a distinct mouth in the same position as the temporary 

 mouth of Bodo saltans, and it is produced into a short passage 

 or gullet leading into the internal protoplasm. By means of 

 this mouth Bodo caudatus can not only swallow bacteria and 

 such like minute nutritious particles, but can also attack other 

 and larger Protozoa, fastening on to them and sucking out their 

 substance. It is estabhshed, then, that the Bodoninse are not 

 only holozoic but also predaceous and carnivorous, and in this 

 respect they offer a strong contrast to the holophytic Euglena. 



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