4] 
the egg, which lies free in the sac cavity at least until fertili- 
zation. The only figure published by Karsten most strongly 
supports this suggestion, showing two absolutely equal cells (the 
synergids!) at the top, while the lower of the two nuclei in 
the sac cavity (the fusion nucleus!) is of about twice the size 
of the upper one (the egg). It is hardly possible to apply to the 
said figure Karsten’s interpretation of one synergid and the egg 
at the top and of two polars in the sac. Moreover my sugges- 
tion gives a reasonable explanation of the three dividing nuclei 
seen after fertilization, these being the egg- and the endosperm- 
nucleus resp. in first and second mitosis. 
Helosis guyanensis (Cuopat et Brrnarp, 1900) very evidently 
claims the formula D—I—4a. The disintegration of the primary 
chalazal nucleus is already to be seen at the two-nucleate stage 
of the embryosac. As a rule the whole nucleus has disappeared 
before the micropylar’s first mitosis. Only once two chalazal 
nuclei have been observed. 
Peperomia pellucida was described by Campset. as long ago 
as 1899 and reinvestigated by Jonnson in 1900. CampBeni. was 
quite sure about the sac being 16-nucleate but he did not suc- 
ceed in tracing the further history of the sixteen nuclei after 
their formation. This gap however is fully filled up by JOHNSON. 
Up to the 16-nucleate stage both authors agree even in details. 
Neither in the two-nucleate stage nor in the four-nucleate one 
any sign of polarity or vacuolation is to be seen: “Die vier 
Kerne sind gleichmassig vertheilt*. Not before eight nuclei are 
well established vacuolation commences. Very soon a large cen- 
tral vacuole is formed and the eight nuclei are found periphe- 
rically. A simultaneous division gives rise to the 16 nuclei of 
the full-grown sac. CampBeLL supposed that afterwards three 
nuclei should come together at the top of the embryosac, for- 
ming the usual egg-apparatus, but he was not quite sure about 
their always numbering three. (His fig. 8 on his Plate XXXI 
reproduces only two nuclei). JoHNsON cleared up the matter 
and there can be no doubt now that there is only one synergid 
besides the egg. A similar group of two cells is found at 
the chalazal end and two other groups lie lateral. The eight re- 
