IV.] 



ZINNIA— PERIWINKLE 



37 



An important character which the stamens present is yet 

 to be noted. If the tube of the corolla of one of the disk- 

 florets be very carefully laid open with the point of a pen- 

 knife, it will be found that the five stamens cohere by their 

 anthers. On this account they are termed symgenesious. 



Fig. 22. Tubular floret of Composite laid open, showing the 

 syngenesious anthers. 



The coherent anthers form a tubular sheath closely sur- 

 rounding the style. The pistil we may infer to be syn- 

 carpous, from its two-lobed stigma, notwithstanding that the 

 inferior ovary is one-celled. 

 In Zinnia you find the — 



Calyx superior^ gaviosepalous. 



Corolla epigyiiotis^ ga77iopetalous. 



Stamens epipetalous^ pe?2ta?idrous, syngenesious. 



Pistil syncarpoiis^ ovary inferior. 



7. Rose Periwinkle ( Vinca rosea). — The calyx is free, 

 but the five sepals are coherent below. The corolla is 



