THE CARPEL AND OVULE 



253 



transverse section shows by its outline, by the arrangement of the 

 vascular strands, and by the position of the ovules that the compound 



-~Ov 



FIG. 198. 



Whole gynoecium of Caltha, 

 consisting of many carpels, all 

 separate. 



FIG. 199. 



Pistil, or gynoecium of Lily, show- 

 ing the relative positions of ovary, 

 style, and stigma. F. O. B. 



structure is referable in origin to three fused leaves (Fig. 201). More- 

 over cases of partial fusion are found, for instance in Colchicum, where 

 the three_ carpels are fused below, but extend upwards as separate 



FIG. 200. 

 Transverse section through the separate 



carpels, composing 

 Caltha. F. O B 



the gynoecium of 



FIG. 201. 



Transverse section of the syncarpous 

 ovary of Lily, showing the three folded 

 carpellary leaves, bearing ovules on 

 their margins. F. O. B. 



styles. Their relative positions are, however, the same as of those 

 in the completely syncarpous^Lily. Biologically the advantage of a 



