From Roland Trimen   10, 13, and 18 October 1863

My dear Sir,

I have today received your very welcome letter of August 27^th.,¹ with the paper on Linum, for which I am very thankful.² I have read the paper with much interest, but have not yet thoroughly studied it. How very astonishing are the marked differences in individuals of one and the same species in the growth and position of the eminently important sexual organs: and, still more, the wonderful fact that the pollen of either form is wholly (or very nearly) ineffectual in fertilising an individual presenting the same modification. To me, the dimorphism presented by Linum and Oxalis seems more difficult to account for than the strangest Orchid modification,³ because of the extraordinary fact that the same great law in constant operation has produced exactly opposite structural modifications in different individuals of the same species,—and that not a plant with separated sexes. By what remarkable process are such conflicting results, so evenly balanced, of natural selection to be accounted for?

The very common White Oxalis (n^o. 1) of which I enclose a specimen is often pink or pink-tinged, and, like the yellow one I sent in my last,⁴ is dimorphic. I gathered 37 flowers at random here and there, and found on examination that in 10 only the stigmas were uppermost; in the remaining 27 the anthers held the superior position.

I was very much delighted to find two other species of Oxalis which are trimorphic. Of the first of these (unfortunately I have preserved no examples) I only gathered 13 flowers (they are white, with narrow crimson edgings to each petal, and, never opening widely, the crimson lines have a beautiful half-spiral effect);—

proportion of 3 forms as follows:

Stigmas lowermost, 3 The leaves of this

〃  central, 7 Oxalis are linear or

〃  uppermost, 3 nearly so.

—

13.

The other, of which I enclose 2 specimens of each form, is pinkish-red, with a wide yellow centre (also a very common species). I found the following to be the relative proportion of the three forms:⁵

Stigmas lowermost, 21

〃  central, 12 N^o. 3.

〃  uppermost, 10

—

43.

I am glad the “peach-puncturing” is likely to be of use, & hope that your renewed strength at Malvern will enable you to give publicity to the evidence it seems to afford in favour of the Moth agency in fertilising the “Scheinsaftblumen”.⁶

With regard to Cypripedium (though it is very likely Asa Gray may be right in his suggestion) I venture to observe that I don’t think your putting in a small bee quite a fair experiment in re the plant’s fertilisation, because it does not appear that the said bee would voluntarily have acted as he twice did under exceptional circumstances.⁷

I have read a good part of Bates’ book, and think it very good,⁸ especially his remarks on the universal predominance of an unmistakeable sylvan type in the whole fauna of Equatorial America.⁹ His remarks on Lepidoptera are especially interesting to me.¹⁰

13^th .— By this mail I received a very kind and interesting letter from M^r. Bates,¹¹ chiefly referring to a few observations I ventured to make on his striking & able paper on the Heliconidæ and their mimickers.¹² I had some difficulty in regarding the Nymphalideous butterflies, with their more or less atrophied fore-legs, as the supreme types or highest forms of Lepidopterous life, but M^r. Bates has most simply explained it to me by the remark that it appears to him “that the more aerial a Lepidopteron becomes, the more perfect it is, and the atrophy of the legs is a sign of less terrestrial habits, &c.” He has kindly offered me a series of Amazonian Rhopalocera, in return for which I hope to supply some gaps in his South African representation of the group

By M^r. Adamson,¹³ the Chief Clerk in the Office where I serve, I have sent you (addressed to care of M^r. Stevens)¹⁴ a bottle of spirit in which are a few Orchid flowers in different stages of growth. I have a few more bottled for you, which I hope to have the pleasure of sending before long, although you warn me in your last letter that you have little hope of being able to work up the accumulation of new Orchid material.¹⁵ Still, in case you ever should have a little leisure, I should be sorry to have missed the chance of affording you some aid, be it ever so little.

I hope you will pardon me for asking you to do me the favour of posting the enclosed note to M^r. Bates. Under the altered postal arrangements, I find my English correspondence somewhat expensive, and yet I do not like to forego the convenience of the regularity ensured by the monthly line of Steamers¹⁶

This morning, and often recently, I have been trying to find some Oxalis seed, but without success. The plants of the yellow species I sent you are plentiful enough,— their flowers are all gone, but I can find no seeds. I found many flowerstalks, the ends of which were brown and shrivelled, from which ends it appeared as if the capsule & part of stalk immediately below it had wasted away. Is there anything unusual in the seeding of Oxalids, or am I merely unfortunate or stupid?

Is not the case of a mule casting a foal very rare? I believe I can furnish you with some authentic details of such a case which recently occurred in this Colony. The foal is now in the Museum,¹⁷ and is a weird-looking object enough. The sire of this still-born oddity is stated by the donor to have been a donkey. Layard has a letter containing particulars,¹⁸ of which I have no doubt I could send you a copy, if it would be of any use.

Wishing you renewed strength for the prosecution of your researches, | I remain, my dear Sir, | Yours very truly, | Roland Trimen.

P.S. (18^th.)— I leave tomorrow on a week’s trip to a part of the country which I have not yet visited. I trust to fall in with some local forms of both Insects & Plants.