Flowers and their Parts 137 



As the ovaries are variously formed, the ovules are placed 



IF 



FIG. 126. I. Stamen of Pinus sylvestris, L., with longitudinal dehiscence 

 (magnified). II. Stamen of barberry, the anther opening by recurved valves 

 (magnified). III. Stamen of Rhododendron, each anther lobe opening by a pore. 

 IV. Stamen of bay, Laurus nobilis, L., with two glands at the base of the fila- 

 ment, the anther opening by recurved valves. V. Stamen of Erica, the anther 

 opening by pores and bearing two appendages at its base (magnified). (From 

 Thom6and Bennett's "Structural and Physiological Botany".) 



in different positions. In the bean they are placed on the 



upper edge of the ovary ; in Orchids, 



Violets, and Drosera the ovary is 



made up of three or five carpels 



which just meet at the edges. The 



joinings make three thick ridges the 



length of the ovary. The part upon 



which the seeds are placed is called 



a placenta,. In Ornithogalum and 



Gladiolus the three carpels curve in 



until they meet at the centre or axis 



of the ovary. In Carnations, " Poor 



Man's Weather - glass " (Anagallis), 



and Portulacaria (Spekboom), the 



ovules are borne on a column, the end 



of the flower-stalk or receptacle; 



they are free from the wall of the 



ovary. 



These three kinds of arrangement or placentation are 

 marginal, which includes the parietal and axile, and " free 



FIG. 127. One-celled swing- 

 ing anthers of Restio. 

 (From Edmonds and Mar- 

 loth's " Elementary Bo- 

 tany for South Africa ".) 



