My dear Sir,

I have to point out a curious mistake in your “Crossing”-book, which I found out too late.¹

You speak of cleistogenous flowers and quote Kuhn’s paper in the Botan. Zeitung 1867, p 65. But here Kuhn as well as later authors (H. Müller f i.) call this form of flowers “cleistogamous”, so that the term corresponds to dichogamous. I found a copy of the Botan. Zeitung and of Müller’s book here in Naples, so that I could refer to them   I have now mentioned it in an Erratum; in a second Edition it has to be altered throughout, I think²   A young botanist, who works here at the station, was struck by my speaking of cleistogenous flowers and Termites, and this made me look at the original paper.

I have to beg your pardon for not having been attentive enough. But as I have not got the Botanische Zeitung myself and as Botany is now rather rich in new terms, I took the word as you had given it.

After rather severe cold for this latitude the spring commences at last. But I scarcely wanted any cheering up, for my work has always been exceedingly nice. D^r Dohrn has done an immense service to science by his Station.³ He desires me to remember him to you and your family.

I have not sent my photo, neither to Haeckel nor to Harting in commemoration of your birthday, because you have it already and because I thought, that you would trust on my most sincere devotion and heartfelt thankfulness for all you have done as a man of science and as the kindest friend, without a public testimonial, which I don’t feel myself worth to give you⁴

Hoping that you have no reason to complain of your health I remain

My dear Sir, | Yours ever sincerely. | J. Victor Carus