ORGAXS OF KEPRODUCTION. 



255 



that arrangement are determined by the number of stamens con- 

 tained in the flower. 



2. Insertion or Position. — When the stamens are free from the 

 calyx and pistil, and arise from the thalamus or torus below the 



Fig. 530. 



Apocar- 

 pous pistil of Ra- 

 nunculus.withtwo 

 stamens arising 

 from the thalamus 

 below it. 



latter organ, as in the Poppy 

 (Jig. 428), and Ranunculus (Jig. 

 520), they are said to be hypo- 

 gynous, which signifies under 

 the female or pistil ; this is 

 the normal position of the sta- 

 mens. Wlien they are attached 

 to the corolla, as in the Primrose 

 (Jig. 531), they are epipetalous ; 

 this is commonly the case when Fig. 

 the corolla is monopetalous. The 

 insertion of the stamens is always 

 regarded as the same as that of 

 the corolla, so that when the 

 former organs are epipetalous their insertion with 

 regard to the pistil depends upon the point 

 where the corolla itself becomes free; thus, in 

 the Primrose (Jig. 531), where the stamens are 

 epipetalous and the corolla arises from below the 

 pistil and free from the calyx, the stamens, as 

 well as the corolla, are said to be hypogynous. 

 When the stamens adhere to the calyx more or 

 less, so that their position becomes somewhat 

 lateral to the pistil instead of below it, as in the 

 StrawbeiTy, Cherry (Jig. 532), and Apricot, they, as well as the 

 corolla are said to be perigynous. When the calyx is adherent 

 to the ovary so that it appears to arise from its apex, the inter- 

 mediate stamens and corolla also arise from the summit, and are 

 said to be epigynousy as in the Campanula (Jig. 533), Epilobium, 

 Carrot, Ixj, &c. 



Fig. 532. Fig. 533. 



Fig. 5S1. Vertical 

 section of a flower 

 of the Primrose 

 {Primula), show- 

 ing epipetalous 

 stamens. The 

 pistil in the cen- 

 tre has an ovary 

 with a free cen- 

 tral placenta, a 

 style, and a capi- 

 tate stigma. 



Fiq 53'' Vertical section of the flower of the Cherry, showing the perigynous 



stamens surroun.ling the pistil. Fig. 533. Vertical section of a flower 



of Campanula, with epigynous stamens. 



