Muller has seen several kinds of
humble-bees and other bees, and Bombylius, visiting the flowers in North
Germany. (1/9. 'Die Befruchtung der Blumen' page 347.)
The results of my trials on the relative fertility of the two forms, when
legitimately and illegitimately fertilised, are given in Table 1.8.
TABLE 1.8. Primula elatior.
Column 1: Nature of the Union.
Column 2: Number of Flowers fertilised.
Column 3: Number of good Capsules produced.
Column 4: Maximum Number of Seeds in any one Capsule.
Column 5: Minimum Number of Seeds in any one Capsule.
Column 6: Average Number of Seeds per Capsule.
Long-styled by pollen of short-styled. Legitimate union :
10 : 6 : 62 : 34 : 46.5.
Long-styled by own-form pollen. Illegitimate union :
20 : 4 : 49* : 2 : 27.7.
(*These seeds were so poor and small that they could hardly have germinated.)
Short-styled by pollen of long-styled. Legitimate union:
10 : 8 : 61 : 37 : 47.7.
Short-styled by own-form pollen. Illegitimate union :
17 : 3 : 19 : 9 : 12.1.
SUMMARY:
The two legitimate unions together :
20 : 14 : 62 : 37 : 47.1.
The two illegitimate unions together :
37 : 7 : 49* : 2 : 35.5.
(*These seeds were so poor and small that they could hardly have germinated.)
If we compare the fertility of the two legitimate unions taken together with
that of the two illegitimate unions together, as judged by the proportional
number of flowers which when fertilised in the two methods yielded capsules, the
ratio is as 100 to 27; so that by this standard the present species is much more
sterile than P.
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