EUPHORBIACE.E 377 



packed together in pairs one above the other, and 

 in the centre at the top, an ovary with three red 

 styles. In an older cyathium some of the anthers 

 protrude beyond the involucre and the stalk of each 

 pair of lobes then appears as red in its upper, white 

 in its lower half; the two separated by a very faint 

 depressed line which in EUPHORBIA HETEROPHYLLA 

 {a plant often grown in gardens and very like POIN- 

 SETTIA but that the uppermost leaves are only half, 

 not entirely red), is a little clearer so that the stalk 

 appears as of two distinct parts, a lower and an 

 upper. In some other species this spot is also marked 

 by a cuplike ring of tissue. It will be seen too, 

 without much difficulty, that the stalks of these anthers 

 are arranged not exactly one behind another but in a 

 zig-zag line, and that mixed with them are a number 

 of filaments or hairs (without anthers). If we take 

 an older cyathium, in the centre of which is a three- 

 angled ovary with three styles, we shall find that the 

 stalk is expanded as a roundish flat red disc on 

 which the ovary itself rests, reminding one a little, 

 though it is much more closely attached to the ovary, 

 of the green calyx seen at the base of the orange 

 fruit. 



The structure of this complicated cyathium may 

 now be easily explained. The central organ is an 

 ovary flower in itself, the red disc just described 

 being all there is of the much reduced calyx (perianth), 

 and the stalk is its pedicel. Each stalked anther 

 is also a flower in itself with one stamen only. The 

 lower white part is the pedicel of the flower, the 

 upper red part the filament of the stamen, and when 



