My dear Gray
Prof. Bessey’s case has come too late for me, as the sheets on this subject are printed off.2 Nor indeed if it had come earlier, should I have known what to do with it. The pollen-grains & stigmas ought to be compared. The case seems to be well worth careful investigation & I wd. have given my eyes for seeds formerly; but now I have done with the subject. If Prof. Bessey likes experimental work he might raise seedlings & fertilise short & long pistils with pollen from long & short stamens from distinct plants & on the same plant: counting the proportion of flowers which set fruit, when fertilised in the various ways & the number of seeds per fruit. His diagram shows the nature & the difference between the flowers excellently. I will send him my book, when published in 4 or 5 weeks, & if he thinks it worth reading he can see how to experimentise on the plants.—3 The case may be one merely of great variability, but it may be one of incipient heterostylism; & under this point of view I would formerly (if I could) have investigated it most carefully.—
When you reeive my little book, you will see that I have done an audacious deed with respect to you.—4
I am now trying to make out the use or function of “bloom” or the waxy secretion on the leaves & fruits of plants, but am very doubtful whether I shall succeed.—5 Can you give me any light? Are such plants commoner in warm than in colder climates? I ask because I often walk out in heavy rain & the leaves of very few wild dicotyledons can be here seen with drops of water rolling off them like quicksilver. Whereas in my flower garden, greenhouse & hot-houses there are several. Again are bloom-protected plants common on your dry western plains; Hooker (Sir Joseph Hooker) thinks that they are common at the C. of Good Hope.— It is a puzzle to me if they are common under very dry climates, & I find bloom very common on the Acacias & Eucalypti of Australia.6 Some of the Eucalypti which do not appear to be covered with bloom have the epidermis protected by a layer of some substance which is dissolved in boiling alcohol.— Are there any bloom-protected leaves or fruit in the Arctic regions?— If you can illuminate me, as you so often have done, pray do so; but otherwise do not bother yourself by answering
Yours affecty | C. Darwin
Please cite as “DCP-LETT-10982,” in Ɛpsilon: The Charles Darwin Collection accessed on