MILKWEED FAMILY 195 
hood-like appendages, each with an incurved horn borne on 
the stamen tube and forming a crown around the stigma 
(Fig. 27, 4); anthers pressing against the lobes of the stigma ; 
the pollen clinging together in tough, waxy or fine-grained 
Fic. 27. Flower of Asclepias syriaca 
A, entire flower; DB, vertical section; C, diagram; D, details of pollen-masses 
and glands. ca, calyx; ¢, corolla; hd, hood; hn, horn; a, anther; s, stig- 
ma; 0, ovary; g, gland; p, pollen-mass. (All considerably enlarged.) 
masses. Ovary free from the calyx tube, of 2 carpels, more 
or less united below but unconnected above; styles 2; stigmas 
5-angled; ovules several-many. Fruit consisting of 1 or 2 
pods. The flowers are very highly specialized for pollination 
by insects (see below, under Asclepias). 
