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MEIOSIS IN GODETIA
329
disturbed meiosis in G. Whitneyi, 4n><fi. Bottae compared will» ineiosis
in G. Whitneyi, 4nXG. def lexa indicates, t hat there are greater
diffe-rences between G. Whitneyi and G. Bottae than between G. Whitney i
and G. deflexa.
The disturbances in Whitneyi, -InXBottae also resnlted in lagging
and elimination of Whitneyi chromosomes. This was nol observed in
Whitneyi, 4ny deflexa. However, in most eases this lagging did not
seem lo depend 011 Whitneyi chromosomes being Univalent, rather it
was a lagging of one of the chromosomes in a II, the other chromosome
passing lo the pole. Such a lagging may probablv result if the II has an
irregulär position in the plate. II seemed these lagging Whitneyi
chromosomes were less readily divided than the Bottae I’s. Concerning the
queslion of differences in the behaviour of Bottae- and deflexa - I’s in
the two triploid hybrids, it may be pointed out that il seemed to be
a fact that the small Bottae chromatids al the begin of the second
division rather offen were hing at a greater distance from Ihe plate.
Perhaps after Ihe disappearance of the nuclear membrane smaller
chromosomes lie at a greater distance from the equator of the spindle,
and consequently need möre time lo reach the plate. The greater
reluctance that was shown by the small I’s in deflexay Bottae to attain
the metaphase 1 plate corresponds lo Ihe behaviour of the small
chromatids at metaphase 2 in Whitneyi 4nyBottae.
Chromosome configurations in interspecific hybrids of Qodetia.
1) Ihe parent species belong to Most common
the same section. configurations: Remarks:
Whitneyi (n = 7)X amoenn (n = 7) (> II + 2 I multivalents may occur, two
II arc strongly heteromorphic.
Whitneyi, 4n X amoenn......... 5 III + 2 II + 2 I the pairing is variable.
Whitneyi X amoenn. amphidiploid
hybrid ...................... Ii II a few uni- and multivalents
may occur.
nutans (n = 14) X Whitneyi..... 7 II + 7 1
nutnns X amoenn............... 5—7 11 + 11 — 7 I multivalents may occur, two
II are heteromorphic.
deflexa (n = 9) X tlottne (n = 9) . . 18 1 9 small and 9 large I’s; allo-II
or auto-Il may occur.
tenetln (n — 17) X - Blauer Zwerg»
(11=17) ..................... 17 II a few uni- and multivalents
often occur.
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