514 BOTANY OF THE LIVING PLANT 



Two antero-posterior stamens (by fission resulting in the four long stamens). 



Two lateral carpels. 



Comparison with the Poppies and the Caper Family shows this to be the 

 probable interpretation of the Cruciferous Flower, and that it is thus referable 

 to a dimerous origin, with regularly alternating whorls. 



ORDER : GERANIALES. 



Family : GERANICEAE. Example : THE FIELD GERANIUM. 



(21) The Field Geranium (Geranium pratense, L.) is a strong-growing herb 

 with opposite, palmate, and stipulate leaves. The inflorescences are lax 

 cymose panicles (Fig. 420). Each flower consists of : 



Calyx, sepals 5, polysepalous, inferior. 



Corolla, petals 5, polypetalous, inferior, alternating with the sepals. 



I. 



FIG. 420. 



Geranium pratense, L. I. whole flower. II. the same in section. III. the stamens 

 at time of dehiscence, the stigmas (s<g) still closely appressed. IV. later stage with 

 stigmas (stg) recurved. V. gynoecium at same stage as IV. VI. ripe fruit dehisced. 

 VII. floral diagram. 



Androecium, stamens 10, free, perigynous, with filaments widened at the base. 

 The five petaline stamens are external, the five sepaline are internal, a con- 

 dition described as " obdiplostemonous," and notable as an apparent departure 

 from the rule of alternation of successive whorls. 



Gynoecium, carpels 5, syncarpous, superior, with single style bearing five 

 distinct stigmas. Ovary with five loculi, each containing two ovules, of which 

 only one usually matures. 



The dry fruit is characteristic. The style remains as a firm woody beak. 

 At ripeness each carpel suddenly splits away longitudinally from the beak, 

 and curving sharply, hurls out its seed to a distance (Fig. 230, p. 288). 



