188 



MORPHOLOGY OF THE ANGIOSPERMS 



Ranales, or advanced form, an adaptation to wind pollination. In 

 Euponmtla (Fig. 72A), connation of the carpels restricts the exposed 

 stigmatic area to the apex of the carpel, and the papillose surface ex- 

 tends downward inside the carpel to and around the ovules, forming an 



Fig. 72. Some primitive carpel types. A, Eupomatia laurina, part of longitudinal 

 section of gynoecium showing connate carpels (spirally arranged) and stigma re- 

 duced to a few papillae on gynoecial "floor"; B, Cimicifuga racemosa, showing early 

 stage in development of style and no definite stigma; C, Drimys membranea, show- 

 ing decurrent stigma, stigmatic crest; D, Caltha palustris, showing slightly decurrent 

 stigma, no style; E, Hydrastis canadensis: El, showing weak style and two-lobed 

 stigma with flaring borders, E2, face view of stigma; F, Dcgcneria viticnsis, show- 

 ing stigmatic crest; G, Chamaewps humilis, open carpel with style; //, Biitomus 

 umbellatus: HI, carpel with style and stylar canal, H2, detail of stylar canal; 7, 

 Coptis trifolia, showing stigma decurrent on style and a long stipe; /, Physocarpiis 

 opulifolius, showing elongate style and terminal stigma. ( F, ajter Bailey and Smith; 

 G, after JuJinke and Winkler.) 



"internal stigma." The restriction here of pollen-tube transmitting tissue 

 to the inside of the carpel, except at the apex, resembles the phylo- 

 genetic shortening of the stigmatic crest by the closure of the carpel as 

 the typical stigma developed. 



The basic form of the carpel is that known, when mature, as the 

 follicle. The follicle is the classical carpel, the form long accepted as 



