CELL DIVISION AND THE FORMATION OF PARAMYLON 
IN EUGLENA OXYURIS SCHMARDA. 
L. B. Walton. 
The method of reproduction in Euglena oxyuris Schmarda 
has not been observed, while the characteristic manner and 
the time element involved in the formation of the constituent 
parts of the cell is also of some interest. Therefore, the following 
notes made in connection with some uncompleted studies on the 
life cycle of Euglena are presented. 
Of the forty or more species constituting the genus, E. oxyuris 
Schmarda is by far the largest, often attaining a length of approxi¬ 
mately 500/x. In the study mentioned, several of the smaller 
species of Euglena had been observed by the writer, to encyst and 
after repeated divisions pass through an apparent sexual stage, 
in consequence of which it was desirable to check the results with 
a larger form, permanent preparations of which could be more 
easily made. Therefore, several specimens of E. oxyuris were 
transferred from a culture to a lens paper aquarium, the margins 
of which were closed by paraffin oil to prevent evaporation and 
placed under observation, Feb. 4, 1906. No reproductive pro¬ 
cesses similar to those in the smaller species mentioned were 
observed, but several in the process of division were noted and 
studied with the 1-12 immersion objective. The characteristic 
organs of the species (Fig. 1, A) are the oval nucleus (n), the 
large anterior (p 1 ) and posterior (p 2 ) paramylon granules, the 
stigma (s), reservoir (r), pharynx (p) and chloroleueites (c). 
The figures are all based on camera lucida drawings. 
On Feb. 6, at 10:03 A. M., a single individual (Fig. 1, B) was 
observed much broader anteriorly than the normal form and in 
which the nucleus had approached the stigma while the anterior 
paramylon granule occupied very nearly the normal position 
of the nucleus. It was not until 1:45 P. M. (Fig. 1, C) that the 
division of the stigma was observed, the nucleus in the meantime 
having become obliquely elongated, and the anterior paramylon 
granule having moved down to a position beside the posterior 
granule. At 3:35 P. M. (Fig. 1, D) division had so far progressed 
that the anterior fourth of the individual—individuals?— were 
separated, the two nuclei being almost distinct. At 4:15 P. M. 
(Fig. 1, E) longitudinal division was nearly complete and the 
two nuclei were moving slowly posteriorly to their normal position. 
At the same time a peculiar phenomenon was taking place in 
connection with the two paramylon granules. The protoplasm 
containing the granule of the individual on the left would rapidly 
flow posteriorly, so that the granule was actually in the posterior 
end of the individual on the right as indicated by the solid arrow. 
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