SOME OBSERVATIONS ON ACINETARIA. 369 
Pl. VII, fig. 5, contained two micronuclear spindles, which 
were slightly smaller than those of the first division. 
Stage D.—This stage is, I believe, represented by Pl. VII, 
fig. 4. In each individual there is one micronuclear spindle 
near the line separating the two individuals, which would 
give rise to the male and female pronuclei. Of the other 
micronuclei, two in process of degeneration lie near the con- 
tractile vacuole, and the third is probably concealed by the 
macronucleus. 
Stage E.—This stage is shown in PI. VII, fig. 5, and the 
details of the male and female pronuclei under a slightly 
higher power in PI, VII, fig. 6. 
At this stage the degenerating macronuclei have become 
enormously drawn out, and as their length is so great, they 
are frequently thrown into coils which may abut on the parti- 
tion dividing the conjugation, and readily give the appearance 
of a macronuclear conjugation. It is to such appearances as 
this that I think Hickson’s account of macronuclear conjuga- 
tion in Dendrocometes paradoxus must be attributed, 
and as Hickson seems inclined to attach much importance to 
this process (vide p. 349: “I am prepared, however, to go 
further than Sand, and regard the presence of the meganuclei 
in the conjugation processes not only as evidence of their 
relation to the interchange taking place in the cytoplasm, 
but as evidence of the necessity of the interchange of mole- 
cules of the substance of the meganucleus itself ’’) it will be 
necessary to examine in some detail the evidence on which 
this meganuclear conjugation rests. This appears to me to 
be contained in the two following passages : 
(1) Page 331. ‘At some time during the last three 
stages (H, J, K) the old meganucleus becomes very large, 
and is bent on itself in the form of a loop or horse-shoe. 
One extremity of this figure passes into the conjugative 
process, and approaching the limiting membrane, traverses 
it and fuses with the corresponding extremity of the 
meganucleus in the other individual. ‘The exact phase 
at which this meganuclear conjugation takes place seems 
