My dear Prof: Oliver,

I am very much obliged for your caution.¹ The case stands thus; I had a plant formerly the early flowers of which never expanded & were of small but not quite uniform size; they produced fine capsules. I thought it was a case of arrested development & did not examine them closely. But when I found on the Ceylon specimens still smaller buds my opinion altered; in these the petals were reduced to excessively minute scales which adhered firmly to the bases of the shorter stamens. Small as these flower-buds were, the anthers had dehisced, & pollen-tubes penetrated the stigmas, which were less papillose than those on the perfect flowers.² These several facts taken together seem to me to justify me in calling the closed flowers cleistogamic; but I should like to hear what you think. Should you be able to find any cleistogamic flowers on any trimorphic species it would interest me greatly to examine them. Hildebrand states in one of his papers that he found cleistogamic flowers on many sp of Oxalis, but he does not say whether they were trimorphic: I think I will write & ask him.³

With many thanks, | Yours sincerely | Charles Darwin