My dear Hooker

I want to ask a question which will take you only few words to answer.— It bears on my former belief (& Asa Gray strongly expressed opinion) that Pipilionaceous flowers were fatal to my notion of there being no eternal her-maphrodites.—² First let me say how evidence goes: you will remember my facts going to show that Kidney Beans require visits of Bees to be fertilised. This has been positively stated to be case with Lathyrus grandiflorus, & has been very partially verified by me.—³ Sir W. Macarthur tells me that Erythrina will hardly seed in Australia without petals are moved as if by Bee.—⁴ I have just met statement that with common Bean, when the Humble-bees bite holes at base of flower & therefore cease visiting mouth of corolla “hardly a bean will set”.

But now comes a much more curious statement that 1842–43 “since Bees were established at Wellington (N. Zealand), Clover seeds all over the Settlement, which it did not before”. The writer evidently has no idea what the connexion can be.—⁵ Now I cannot help at once connecting this statement (& all the foregoing statements in some degree support each other, as all have been advanced without any sort of theory) with the remarkable absence of Papilionaceous plants in N. Zealand.—

I see in your list Clianthus, Carmichælia 4 species— A new genus, a shrub; & Edwardsia—(is latter Papilionaceous?)⁶ Now what I want to know, is, whether any of these have flowers as small as clover; for if they have large flowers they may be visited by Humble-Bee, which I think I remember do exist in N. Zealand;⁷ & which Humble Bees would not visit the smaller clovers.— Even the very minute little yellow Clover in England has every flower visited & revisited by Hive Bees, as I know by experience.—⁸ Would it not be a curious case of correlation if it could be shown to be probable that herbaceous & small Leguminosæ do not exist because when seeds washed ashore!!!⁹ no small Bees exist there. Though this latter fact must be ascertained! I may not prove anything, but does it not seem odd that so many quite independent facts, or rather statements should point all in one direction viz that Bees are necessary to the fertilisation of Papilionaceous flowers.

Ever yours | C. Darwin

My man is getting on with D. Candolle, but he has been unavoidably delayed a little.—¹⁰ R. Brown’s Prodromus N. Hollandiæ has so very few varieties, that I sh^d not dare to trust result, whatever it might be.—¹¹