STUDIES UPON AMOEBA 
313 
described is so exact as to leave no doubt that the former are de- 
rived from the latter. They are amoebo-flagellospores of the 
Amoebae. 
The flagellospores occasionally divide by binary fission (figs. 
36 and 39), but always, so far as I have observed, first drawing 
in their flagella. One cannot therefore say what constant rela- 
tion, if any, exists between the plane of division and the position 
of the flagella. This binary fission is not very common. One 
sometimes searches for hours without finding a dividing individ- 
ual. Again several may be found in one field of the microscope. 
One not infrequently sees two flagellate individuals come into 
contact (figs. 40, 41 and 42). Sometimes they seem to pay no 
attention to one another. In other instances they apply them- 
selves closely to one another by their anterior ends, drawing in 
their flagella, and while still clinging together anteriorly constantly, 
though slowly, changing the form of the posterior ends of their 
bodies (flg. 41). In a considerable majority of the cases observed, 
the animals separated after a period of contact varying from two 
or three minutes to half an hour. I have but once followed the 
process of copulation through from the beginning to its comple- 
tion. In this instance the biflagellate isogametes met, pulled 
in their flagella, and became fused by their non-granular anterior 
ends (fig. 42). Gradually the bodies became completely fuse.i 
and the zygote, a typical Amoeba of the blattae type (fig. 42, e), 
crawled slowly away. It soon, however, changed its form, devel- 
oping pointed pseudopodia (fig. 42 f). Its behavior was not fol- 
lowed further. I have several times, probably a dozen times, 
observed what was probably the completion of copulation, al- 
ready begun before these animals attracted attention. The ani- 
mals have been studied at all hours of the day and night and at 
no time is conjugation frequent. In one field of vision, with an 
inmaersion lens, hundreds of these minute flagellates may be pres- 
ent. It seems strange that instances of copulation are not more 
frequent. 
The question of the fate of the Amoeba after its gemmules are 
set free is an interesting oae which I cannot answer. When these 
