THE FLOW I'm 105 



But tlie name applies even 



l.'J4. The several distinct pistils of a 

 single fidwer. One cut across, 

 and one cut length\\'ise, to show 

 the placentation. 



of some sort (see Fig. l-!8 

 when no special outgi jwlh 

 is to be seen. 



192. Types of ovary and 

 placentation. — When the pis- 

 tils are separate and tlie ovaries, 

 therefoi'e, one-celleJ, the tj'pical 

 arrangement of tlie ovules in 

 each ovary is in a double verti- 

 cal row on the side nearest the 

 cei'ter of the flower (Fig. 1:!4). 

 A solitary ovule may be sus- 

 pended from the top of the 

 cell, or spring from the side 

 toward the flower axis, or rise from the bottom. 



193. When the pistil is compounded of several carpels, various 

 arrangements ot the parts are possil)le. The common one is that 



194. With two or more cells 

 and axile placentation (Figs. 1.3.5- 

 137). — Such a pistil is just what 

 would be formed if simple pis- 

 tils, like those .of the Larkspur, 

 pressed together in the center 

 of the flower, were to cohere by 

 their contiguous faces. In such 

 a case the placentas are naturally 

 axile, or all lu'ought together in 

 the axis or center. The ovary 

 lias as many internal jiai'titions, 

 or t/i^s/'pititrnls, as tlipre are car- 

 ]iels in tlie coniposilion. \\'1i(Mi 

 such pistils I'ipen into pods 

 they often separate along these 

 lines into their elementary car- 

 pels. 



195. One-celled, with parietal placenta (Figs. 138, l:!!)). — In this 

 not uncommon case it is conceived that the several original cai'pellary 

 cavities are thi-own into one as llie orgai; grows. The ovules now 

 spring from the lines of junction (it the ililtVrent carpels. A placenta 

 belongs here half to one carpel, half to annlher. At each placenta a 

 double row of ovules is apt to be found; but the two rows originate 

 from distinct ca,rpels. I'he number of oar])els is still to be told fi'om 

 the number of pilacenta;. The placentation is here termed parietal. 



130 



l:i.5-i;;7. Pistils: 1.3.5, a Saxifrase, tlie 

 carpels or simple jiistils unitetl 

 below, free above; l.'Hi, counnon 

 St. .Johnswort, the styles of the 

 carpels distinct ; 1)'>7, anotlier St. 

 Johnswort, the carpels united 

 throughout. 



