My dear Sir

Many thanks for your letter.¹ I stand indeed to you under very great obligations for your kindly sending me all your publications and I should have long ago written to you to thank you, had I not been afraid of giving you more trouble by my letters, than my thanks would be worth.² That your papers were most useful to me and others here, you will see from the account, which I gave of some in connexion with some other publications, which your observations and hypotheses elicited.³ The account, which I add, is accompanied with a few lines on those peculiar appearances, of which I am now convinced that they are caused by a sort of hybridism in consequence of grafting. The account is published in: Schriften der physikalisch-œkonomischen Gesellschaft zu Koenigsberg Jahrgang VI Sitzungsberichts, p. 4.⁴

The account of what I said on the same subject at the Amsterdam-congress—is printed about 4 or 5 months ago but has not yet been published.⁵ At the time I corrected the letterpress, which Professor Rauwenhoff⁶ at Rotterdam sent me, being the editor of the transactions of that congress. I write at once to Professor Rauwenhoff to tell him, that he might send you directly a copy; I have none. The transactions of that Congress will be published in 8^o.⁷

I collected material or rather was allways at the look-out for material for more than 10 years on the hybridization and muling by grafting. The case of Cytisus Adami I had an opportunity of examining in a most perfect development at Bonn—⁸ As regards the Bizarrin⁹ I saw no case, nor any person living, who ever had observed one, except Professor Passerini at Parma,¹⁰ who is about of procuring me one or two trees, which exhibit Bizarrin, but I am afraid our climate will be too severe for it, as it is for Cytisus Adami.

If I had 3 or 4 weeks to spare I should prepare a full paper on the matter, not being able at present to add any thing. But I shall not have time to do so before 2— or 3 months have elapsed, as I am very hard at work to finish some papers on Nymphaeaceae, which I promised to Professor Miquel and V. Martius.¹¹ Having finished those papers I took the resolution of writing down at full length my observations on Cytisus Adami and similar subjects. The account on them which I gave at the Amsterdam Congress is a very brief one.¹²

At the close of the paper, I add, I mentioned the seeds of Euryale, ripened by flowers, which remained under water and did not open.¹³ Now I got last year many of that description and some allready germinated.

I take the liberty of adding my photography and asking for yours—¹⁴ You could do me no greater favor, than if you would send it me.

Yours most respectfully and faithfully | R. Caspary