COMMON MILKWEED 



soon as the flower opens, and press closely against the 

 flower-stalk. Indeed, they take themselves out of the 

 way so thoroughly that one almost forgets they are 

 there, at any rate it is the hoods and horns of the 

 corona that attract attention. This corona consists 

 of five hooded cups, nectaries, with an incurved horn 

 in each. Within this circle of honey-jars are the five 

 stamens, difficult to separate because of their peculiar 

 growth and arrangement. They grow from 

 the base of the corolla, and the filaments 

 connect with each other and surround the 

 pistil which consists of two carpels. Not 

 only do they surround the pistil, the an- 

 ther-sacs have inlooking scarious tips which 

 unite and form a five-sided disk. The whole 

 stamen system has been compared to a cup, 

 upside down, standing in the midst of the 

 flower; the sides being the filaments of the ^^Zlf 

 stamens, and the top the united tips of the 

 anthers. The pollen of each anther is collected into a 

 club-shaped mass which is joined to a similar mass 

 formed by the pollen of the next anther. Thus the 

 connected pollen mass that looks like two clubs joined, 

 belongs to two separate stamens, which stand side by 

 side. This entire arrangement shows very clearly and 

 can be most easily studied in a fading flower. 



The pistil has an ovary of two carpels with two 

 short styles united at their summits by a five-lobed 

 stigmatic disk. In order to get a complete compre- 

 hension of the flower it is well to study it in bud, in 

 full flower, and when about to fall. 



The polHnation of the flower has been clearly pointed 

 out by Muller, as follows: 



IS9 



