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May 24th 1862

Cabbages Prepotency

10˚. 45' put plenty of own pollen on 3 lately opened flower already apparently with own pollen on, of Ragged Jack; & next day after 23 hours put pollen of long stamen of Cattells' early Barnes Barnes Cabbage plant growing at great distance apart.— & marked with black thread; as these flowers were left exposed & remained open for a day or two could probably received own pollen by insects.

Serve to show that in var. said not to be easily crossed even late application of pollen produce effect—

[Right margin:] Prepotency of pollen of other Var. Quoted

do. put plenty of own pollen on 3 open flowers of "Cattells early Barnes' Cabbage" & after 23 hours put pollen of long stamens of Ragged Jack. — marked with black thread. Same remarks applicable in this case as in last. — (Plants killed)

June 4th castrated 4 flowers of Ragged Jack Stems nearest to Greenhouse & put under net: 6' fertilised 2 with pollen of short stamens of Cattells Early Barnes ↘

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Cabbage & marked with black thread; & 2 with pollen of long-stamens marked with white thread — 7th refertilised them — but pollen not very good

These produced miserable little pods with no seed.

Two pods from 1st experiment. From one 7 young cabbages were raised 5 pure ragged Jack & 2 strongly crossed with Barnes. — From the other pod 8 plants were raised 7 pure & 1 crossed; so that altogether 15 plants were raised, of which 12 were pure & 3 strongly crossed. This would indicate that that in old experiments in natural crossing of cabbages that the number of crossed plants was due to foreign pollen being incessantly brought; but yet, I think, must have some prepotent effect to account for so many.

We see anyhow that several application of pollen is necessary

The plant own pollen must by gravity or thrips be incessantly brought, as plant under net seeds so perfectly.—

[in margin:] It is very odd that the all the crossed plants, pure & impure in pot were more vigorous could this be accident or result of cross.— Dichogamy