[308]

Jun 16th

Oxalis rosea

[data not transcribed]

(Used)

[308v]

[text excised]

pollen-grains of many plants, or the irritability of the stamens which move when touched by insects &c.— as all these contrivances are evidently adaptations for favour or ensureing cross-fertilisation.

All ordinary flowers are always so far open that insects can & do force an entrance into them; notwithstanding that some, like the snapdragon (Antirrhinum), various Papilionaceous and Fumariaceous flowers, are in appearance closed. The existence of It cannot be maintained that their openness of flower is necessary for their fertility for cleistogene flowers shows prove

[Cross and self fertilisation, p. 375: "I need say nothing here of the endless contrivances, such as the viscid glands attached to the pollen-masses of the Orchideae and Asclepiadae, or the viscid or roughened state of the pollen-grains of many plants, or the irritability of their stamens which move when touched by insects etc.—as all these contrivances evidently favour or ensure cross-fertilisation.
All ordinary flowers are so far open that insects can force an entrance into them, notwithstanding that some, like the Snapdragon (Antirrhinum), various Papilionaceous and Fumariaceous flowers, are in appearance closed. It cannot be maintained that their openness is necessary for fertility, as cleistogene flowers which are permanently closed yield a full complement of seeds."]

[309]

17th O. rosea continued

[data not transcribed]

(Used)

[309v]

*(a) page 42

Mr. Blackley observed that the ripe anthers of rye did not dehisce whist kept under a bell-glass in a damp atmosphere, whilst other anthers exposed to the same temperature in the open air dehisced freely. He also found much more pollen adhering to the sticky slides, which were attached to kites and sent high up in the atmosphere, during the firsy fine and dry days after wet weather, than at other times:

Experimental Researches on Hay Fever, 1873. p. 127.

[Cross and self fertilisation, p. 376, n*: "Mr. Blackley observed that the ripe anthers of rye did not dehisce whilst kept under a bell-glass in a damp atmosphere, whilst other anthers exposed to the same temperature in the open air dehisced freely. He also found much more pollen adhering to the sticky slides, which were attached to kites and sent high up in the atmosphere, during the first fine and dry days after wet weather, than at other times: 'Experimental Researches on Hay Fever' 1873 page 127."]