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MEIOSIS IN GODETIA
323
Canyonville gr. and Magalia, had been used in the crosses. The hybrid
Canyonville gr. "Xhispidula had a weak pairing, 2 11 + 17 I being the
niost common configuration (fig. 1). P.m.c.’s with 1 111+2 11 + 14 I
or with 21 1 (fig. 3) were rather often observed, other configurations
were möre rare. At anaphase 1 the I’s do not divide. Lagging and
elimination of I’s may occur, but in view of the high number of I’s
such disturbances must be considered to be relatively rare. At anaphase
2 all chromosoines divide.
Meiosis in nutans MagaliaXhispidula was different in some aspects.
This was expected, because meiosis in WhitneyiXnutans Magalia shows
differences from meiosis in other hybrids between G. Whitneyi and
G. nutans: some plants had 22 chromosoines, at metaphase 1 a
trivalent was often observed, and rather often inöst or all I’s were in or
near the equatorial plate (Håkansson 1942). In nutans
MagaliaXhispi-dula the chromosome pairing was better than in nutans CanyonvilleX
hispidula, fig. 2 shows 1 HI + 4 11+10 I, and the tendency of the Fs
to be in the equatorial plate seemed to be stronger. 7 II+ 7 I were
never observed.
It seems verv doubtful that G. hispidula is the second paren! species
of G. nutans.
Godetia Whitneyi 4nXG. Bottae. It is of some interest to
com-pare meiosis in G. Whitneyi, 4nXG. deflexa and G. Whitneyi, 4nX
G. Bottae. G. deflexa and G. Bottae are by laxonomisls considered lo be
closely related, they have the same chromosome number but the
chromosoines of deflexa are several times larger than the chromosoines of
Bottae. G. deflexa is a higher, möre robust type, G. Bottae being möre
slender. In the hybrid G. deflexaXG. Bottae the chromosome pairing
is weak hut a few II’s may be formed through allosyndesis or möre
seldom through autosyndesis (IL, 1943 b). The diploid hybrid G.
Whit-neyiX G. deflexa forms as a rule lß I’s, in rnany p.m.c.’s most or all
I s are in an equatorial plate, hu| as a rule they do not divide at
anaphase 1 (IL, 1941b). The triploid hybrid G. Whitneyi 4nXG. deflexa
bas 7 11 + 9 I, the I"s being deflexa chromosomes. Here the Fs möre
regularly are in the equatorial plate forming a circle surrounding the
II’s, and in this hybrid the I’s regularly divide at anaphase 1, when the
homologues of the Il s have arrived to the poles. The numerous
disturbances that characterize meiosis of the diploid hybrid, do not occur
here. Failure of Fs to attain the metaphase 1 plate or of chromatids to
attain the metaphase 2 plate may, however, sometimes occur, and eli-
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