On the Aestivation in the Cyathium of Euphorbia fulgens, with some Remarks on the morphological Interpretation of the Cyathium in General

A. Euphorbia fulgens. 1. The aestivation of the cyathium appendages is SW (= short way) heterotropically contort. When in some cyathia the aestivation is less regular, and an individual appendage is wholly overlapping, this is usually appendix a, between the involucral bracts 1 and 3, sometimes b, between the bracts 1 and 4. 2. The aestivation of the involucral bracts usually is LW heterotropic. In a minority of cases the aestivation is different; the departures from contortion are nearly always returns to eutopy, even so much that in a considerable minority of cases a complete eutopic aestivation is reached. 3. The facts reported sub 1 and 2 give a fresh support to the views expressed earlier about the determination of the contortion direction in heterotropic aestivation. At the same time they give new evidence for the classic theory of the cyathium. B. The cyathium in general. 4. The view of Haber that the glands represent cauline structures is to be discarded. 5. The view of Gluck and Troll that the glands are phyllomes of which the appendages represent the laminas and the involucral bracts the stipules, is not to be accepted. 6. The view of Schmidt and Haber that the male partial inflorescences in the cyathium of Euphorbia are dichasia with monochasial endings, is not supported by any facts. 7. The classic theory of the cyathium, as expounded by Eichler, is to1 be maintained.